f a parent entity is applying for the Phase 3 General Distribution on behalf of itself and multiple subsidiaries, and the parent and subsidiaries file a group tax return, should the parent entity submit the joint tax return as part of its application?

Yes. Similar to the Phase 2 General Distribution application, in cases where a parent files a group tax return for itself and all/or some of its subsidiaries, the parent entity should submit the group tax return that includes all subsidiaries on behalf of which the parent entity is applying.