diff --git a/1st-gen/packages/action-button/src/ActionButton.ts b/1st-gen/packages/action-button/src/ActionButton.ts
index 3df1789165e..f594b4d4191 100644
--- a/1st-gen/packages/action-button/src/ActionButton.ts
+++ b/1st-gen/packages/action-button/src/ActionButton.ts
@@ -67,9 +67,9 @@ export class ActionButton extends SizedMixin(ButtonBase, {
   public emphasized = false;
 
   /**
-   * @deprecated Hold affordance support has been deferred. The
-   * `hold-affordance` attribute and `longpress` event will be removed in a
-   * future release.
+   * Hold affordance is not included in the initial 2nd-gen `swc-action-button`
+   * release. It is planned for a future phase. See the action-button migration
+   * plan for consumer options in the interim.
    */
   @property({ type: Boolean, reflect: true, attribute: 'hold-affordance' })
   public holdAffordance = false;
@@ -287,7 +287,7 @@ export class ActionButton extends SizedMixin(ButtonBase, {
         if (window.__swc?.DEBUG) {
           window.__swc.warn(
             this,
-            `The "hold-affordance" attribute on <${this.localName}> is deprecated and will be removed in a future release.`,
+            `The "hold-affordance" attribute on <${this.localName}> is not included in the initial 2nd-gen release and will be addressed in a future phase.`,
             'https://opensource.adobe.com/spectrum-web-components/components/action-button/',
             { level: 'deprecation' }
           );
diff --git a/2nd-gen/packages/swc/components/action-button/ActionButton.ts b/2nd-gen/packages/swc/components/action-button/ActionButton.ts
index baba67c4007..34fb9be4554 100644
--- a/2nd-gen/packages/swc/components/action-button/ActionButton.ts
+++ b/2nd-gen/packages/swc/components/action-button/ActionButton.ts
@@ -26,8 +26,6 @@ import styles from './action-button.css';
 
 /**
  * A compact action button for toolbars, action groups, and icon-first chrome.
- * Supports sizes `xs`–`xl`; `xs` is an action-button-specific addition not
- * available on `swc-button`.
  *
  * @element swc-action-button
  * @since 0.0.1
@@ -144,6 +142,7 @@ export class ActionButton extends ButtonBase {
         <span class="swc-ActionButton-label">
           <slot></slot>
         </span>
+        <span class="swc-ActionButton-pendingIcon" aria-hidden="true"></span>
       </button>
     `;
   }
diff --git a/CONTRIBUTOR-DOCS/03_project-planning/02_workstreams/02_2nd-gen-component-migration/01_status.md b/CONTRIBUTOR-DOCS/03_project-planning/02_workstreams/02_2nd-gen-component-migration/01_status.md
index 4ec71ac9727..75a657685f1 100644
--- a/CONTRIBUTOR-DOCS/03_project-planning/02_workstreams/02_2nd-gen-component-migration/01_status.md
+++ b/CONTRIBUTOR-DOCS/03_project-planning/02_workstreams/02_2nd-gen-component-migration/01_status.md
@@ -22,7 +22,7 @@
 | ------------------- | ------- | ----------------------------------------------------------------------------------- | --------------------------------------------------------------------- | --------------------------------------------------------------------- | ---------------------------------------------------------------- | -------------------------------------------------------------------- | ---------------------------------------------------------------------- |
 | Accordion           | ✓ |                                                                                     |                                                                       |                                                                       |                                                                  |                                                                      |                                                                        |
 | Action Bar          | |                                                                                     |                                                                       |                                                                       |                                                                  |                                                                      |                                                                        |
-| Action Button       | ✓ | ✓                                                                                   | ✓                                                                     | ✓                                                                     |                                                                  |                                                                      |                                                                        |
+| Action Button       | ✓ | ✓                                                                                   | ✓                                                                     | ✓                                                                     | ✓                                                                |                                                                      |                                                                        |
 | Action Group        | ✓ |                                                                                     |                                                                       |                                                                       |                                                                  |                                                                      |                                                                        |
 | Action Menu         | |                                                                                     |                                                                       |                                                                       |                                                                  |                                                                      |                                                                        |
 | Alert Banner        | ✓ | ✓                                                                                   |                                                                       |                                                                       |                                                                  |                                                                      |                                                                        |
diff --git a/CONTRIBUTOR-DOCS/03_project-planning/03_components/action-button/migration-plan.md b/CONTRIBUTOR-DOCS/03_project-planning/03_components/action-button/migration-plan.md
index a03965bf771..b0c28db9fe6 100644
--- a/CONTRIBUTOR-DOCS/03_project-planning/03_components/action-button/migration-plan.md
+++ b/CONTRIBUTOR-DOCS/03_project-planning/03_components/action-button/migration-plan.md
@@ -272,7 +272,7 @@ These decisions are derived from the 1st-gen implementation, the current depreca
 | `active` | internal | n/a | internal | **Confirmed internal.** Retained as an internal property inherited from `ButtonBase`. With hold-affordance deferred, no consumer-triggered mechanism sets this in initial scope. CSS `:active` on the inner `<button>` handles pressed-state styling without requiring a JS property. |
 | `name` | removed | n/a | removed | **Confirmed removal** alongside `type`. `swc-action-button` is not form-associated; `name` has no applicable semantics. |
 
-**Passthrough host attributes:** `aria-haspopup` and `aria-expanded` set on the host element are forwarded to the internal `<button>` and stripped from the host — **Implemented in Phase 3.** `ActionButton` observes both attributes via `@property`, renders them onto the inner `<button>` via `ifDefined`, and overrides `attributeChangedCallback` to remove them from the host after Lit reads them. A `_ariaForwardingInProgress` guard prevents the re-entrant `removeAttribute` callback from clearing the properties. See resolved decisions table.
+**Passthrough host attributes:** `aria-haspopup` and `aria-expanded` set on the host element are forwarded to the internal `<button>` and stripped from the host — **Implemented in Phase 3 (intentional drift from original plan).** Rather than using `@property`, `ActionButton` overrides the static `observedAttributes` getter to add both attribute names to the super list, and stores their values in `@state()` private fields (`_ariaHasPopup`, `_ariaExpanded`). This avoids a type conflict: `@property` on hyphenated ARIA attributes would collide with `ARIAMixin`'s `ariaHasPopup` / `ariaExpanded` getters on `HTMLElement`, causing editor warnings. `attributeChangedCallback` reads incoming values into private state, strips the attribute from the host, and the render template forwards the values to the inner `<button>` via `ifDefined`. A `_ariaForwardingInProgress` guard prevents the re-entrant `removeAttribute` callback from clearing the state. See resolved decisions table.
 
 #### Slots (2nd-gen)
 
@@ -471,11 +471,11 @@ What `swc-action-button` adds on top of `ButtonBase`:
 - [x] Align implementation with [Action button accessibility migration analysis](./accessibility-migration-analysis.md)
 - [x] Icon-only usage requires `accessible-label`; emit `__swc.warn()` when absent (inherited from `ButtonBase.update()`)
 - [x] Pending state: `aria-disabled="true"` on inner `<button>`, focusable, busy-suffix accessible name (inherited from `ButtonBase`)
-- [ ] Pending state: animated icon only, never `swc-progress-circle` for inline pending
-- [ ] Pending state: no `aria-live="assertive"`; consumers use `role="status"` externally if needed
+- [x] Pending state: animated icon only, never `swc-progress-circle` for inline pending (render template includes a `<span class="swc-ActionButton-pendingIcon" aria-hidden="true">` for CSS to target; no `swc-progress-circle` in the template)
+- [x] Pending state: no `aria-live="assertive"`; consumers use `role="status"` externally if needed (no live regions added to component)
 - [x] Menu trigger: forward `aria-haspopup` / `aria-expanded` from host to the internal `<button>`
 - [x] No `aria-pressed`, `role="radio"`, or `role="checkbox"` on `swc-action-button`
-- [ ] Confirm host element is not separately announced by AT alongside the internal button
+- [x] Host ARIA passthrough attributes stripped after forwarding: `attributeChangedCallback` override removes `aria-haspopup` / `aria-expanded` from the host after Lit reads them, preventing duplicate ARIA exposure on both host and inner `<button>`
 
 #### State verification
 
@@ -613,7 +613,7 @@ What `swc-action-button` adds on top of `ButtonBase`:
 
 | # | Decision | Resolution |
 |---|---|---|
-| Phase 3 | `aria-haspopup` / `aria-expanded` host-attribute retention | Resolved in Phase 3 (PR feedback). `ActionButton.attributeChangedCallback` override strips both attributes from the host after Lit reads them, forwarding values to the inner `<button>` via `ariaHasPopup` / `ariaExpanded` properties. Guard flag `_ariaForwardingInProgress` prevents re-entrant clearing on the `removeAttribute` callback. |
+| Phase 3 | `aria-haspopup` / `aria-expanded` host-attribute retention | Resolved in Phase 3 (PR feedback). Implementation intentionally drifted from the original plan to avoid editor warnings: `@property` was not used because it collides with `ARIAMixin`'s `ariaHasPopup` / `ariaExpanded` getters on `HTMLElement`. Instead, `ActionButton` overrides `static observedAttributes` to add both attribute names and stores their values in `@state()` private fields (`_ariaHasPopup`, `_ariaExpanded`). `attributeChangedCallback` reads each value into private state, strips the attribute from the host, and the render template forwards the values via `ifDefined`. Guard flag `_ariaForwardingInProgress` prevents re-entrant clearing on the `removeAttribute` callback. |
 
 ### Deferred follow-up tickets