I haven't read anything official, or even "semi-official" which says park hopping won't be allowed. The posted park schedule screams "hop over to EPCOT the end of the day for dinner, shopping and drinking" Maybe you won't be able to get a reservation but will have to check
MDE and see if EPCOT is accepting new guests.
I've seen pictures of masks with a flap. Suggested use is to drink wine with a straw.
Posters are reading too much into posted CM openings at restaurants and resorts. No question this is for the first phase of opening, only DVC resorts. I'm sure additional restaurants will open as Disney opens up the resorts to "regular" guests.