I think comprehensive is a strong word. Sometimes the reviews are helpful, sometimes they aren't. Also, you can have up to 4 reviews, but that's unlikely. 3 is most common, but don't read anything into the number of reviews (unless it's 0).
True.
Based on previous years, I'm expecting either (all early morning): Friday 3/27, Tuesday 3/31, or Friday 4/3... But, as with all things NSF it could be ????
Is there anywhere that elaborates on their rationale for this? Most of the faculty that I've spoken with have expressed frustrations that it doesn't come out sooner.
For the GRFP? If it's just another NSF panel, then NSF can have other panels during that time, they award many grants.
Not disagreeing that it will likely be in April, but I'm struggling to understand your logic.
I spent about $20 to get two books: the Kaplan book (with like 5 practice tests) and a Barron book of just practice tests. Also used the free Magoosh flashcards app. There are also many free resources online for just about anything (like explanations to most quantitative problems).
I would first take a practice test of some sort. ETS offers two (or 3, I'm not sure) practice tests on their website using similar software to what the GRE uses. Start there, see where your score is relative to where you want it to be and figure out how much you really need to study. After that, I would strongly recommend practice sets of whatever you're struggling with. If it's verbal vocabulary, I would recommend doing flashcards. You can either make your own or use one of the many flashcard apps out there. If you're trying to get an excellent verbal score (say >162/3), then you should know that and start going through flashcards now.
When is your test scheduled for?
Kaplan 1 (paper): 155Q, 155V
Kaplan 2: 164Q, 158V
Kaplan 3: 170Q, 160V
Kaplan 4: 167Q, 160V
Kaplan 5: 167Q, 160V
Powerprep 1: 167Q, 165V
Real: 170Q, 168V
Total time studied: ~110 hours, took ~1 practice test a week for 5 weeks before GRE. Took two the weekend before.