We didn’t expect Galaxy’s Edge at Walt Disney World to open until late fall originally, but even if Disney Parks waited and didn’t open things until originally planned, it seems Rise of the Resistance still would not have been ready, which may explain why the lands were opened early to begin with.
Both of the new lands were actually given opening dates in advance of their original windows.
The only date given when the “second phase” of Galaxy’s Edge was announced was “later this year” and it seems that things have taken even longer than anticipated, as, in the case of Disneyland, that broad window will actually be missed.