BEST GUESS - Here's my best guess on how the 4 hour window will work. (I can't account for the overlap of times)
Group 1 (8am-12pm) - will just enter into the yellow area since they don't have to wait on anyone ahead of them. They'll be scanned and checked to make sure they belong and given a colored wristband to wear. Go fly the Falcon!
Group 2 (12pm-4pm) - they will allowed to enter the Critter Country entrance, again scanned to make sure they belong and given a different colored wristband than group 1. They will be allowed to enter ans be 'staged' over on the RotR side. They will have access to the shops, restrooms on that side of the land, while they wait to enter. They can not enter the Village/Falcon area until 12pm
Group 3 (4pm-8pm) - they will be allowed to line up outside of the Critter Country entrance, but can not enter the 'staging' area. CMs will start scanning and issuing a 3rd color wristband while they wait.
...pretend that 12pm is coming soon. Guessing at about 11:45am CMs will start sweeping the land and ushering Group 1 guests out of the land. No one will be allowed to get in line for the Falcon ride. Once CMs are satisfied that Group 1 is out, they will usher Group 2 over to the Village/Falcon side of the land and they can begin to queue for the Falcon, and check out the food, merchandise, etc.
...after Group 2 has moved to the Village/Falcon side of the land, Group 3 will be allowed inside the Critter Country entrance and they will be 'staged' just like Group 2 was, and can explore the shops, have restroom access, while waiting. They can not enter the Village/Falcon area until 4pm.
Doing it this way, Group 2 and Group 3 actually could get 8 hours in the land. 4 Hours waiting in the 'staging' area and 4 hours in the Village/Falcon area itself, unless Disney won't let them queue and 'stage' for that long.
Again, just my GUESS. - Thoughts?!?
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