I was under the assumption that
Genie+ could be only every two hours until someone here pointed me over to the video from Molly. I watched and rewatched and my understanding based on that is that your next Genie+ reservation can be made as soon as you check into your current attraction, and that the next reservation does NOT have to be two hours away as long as you've checked in. I still don't trust any of this info until I see it in practice next week.
Based on everything I've read/seen, here's how I THINK G+ will work:
When you make your first LL selection, it will show you all the available rides. Each will have one time shown (the next available time).
If your first LL selection made through G+ is between 1-119 minutes in the future, you will be able to go on G+ and look for your next one as soon as you scan in to the ride. At that time, you'll again see the next available time for all G+ rides.
Some of the more popular rides will have the return times pushed later more quickly (just like it was with legacy paper FP). So, if you are choosing a popular ride for your 2nd or 3rd choice, it might be 120+ minutes in the future. In this instance, you would not have to wait until scanning in to get your next LL selection on G+ but, rather, you'd be able to get another one once two hours has elapsed.
If you have a LL return time that's far in the future (which could theoretically happen for some of the most popular rides), you would be able to obtain another LL after two hours and if the one you select has a quick return time, you could get another as soon as you scan in for that ride (with your evening LL still "stacked" in reserve). If you keep selecting rides with return times that are not too far in the future, you'll be able to maximize the number of LLs you obtain.
However, if you're holding that late afternoon LL time and after two hours you select another popular ride where the return times have also extended into later hours, you'll need to wait another two hours before making another LL selection in G+. Doing this would give you two "stacked" LLs for later, but also increases the odds that you'll get a fewer number of overall LLs, because while you're in those two hour cooling off periods, the return times for other rides are also moving into the future.
The big unknown is how quickly non-headliner LLs will get booked up. If the usage is somewhat consistent with FP+, there should still be choices well into the afternoon for some rides, but headliners will be booked up earlier.
So, which strategy will people land on as the "best" (subjective for each individual, I know)? Book headliners even if the return times are later and take your chances on getting fewer LLs for the non-headliners? Or avoid those later return times in order to get more LLs per day? I'm thinking that seeing the return time already pushing later will be a strong motivator for some people to select certain rides (on top of the popularity) and folks (at least those "in the know") will be more inclined to incur the two hour cooling off period to ensure they have a LL reservation for rides that they anticipate will have the longest SB waits.
ETA: I think the jury is still out on whether the two-hour cooling off period goes into effect for a 7 am selection (or even later for parks that open later). If the park opens at (or before) 9am, it shouldn't matter because any LL reservation you make at 7 am will be for shortly after park open, so you'd be able to make another one shortly after 9am (possibly even earlier if your first LL selection has a return time before 9am.
If EPCOT eventually returns to a 9am opening, this will be moot, but with 11 am opening, the big question is whether you can make another LL at 9am (two hours cooling off period after you selected the first one at 7 am) or if you'll have to wait until the park opens before making your next LL selection in G+.
