I'm saving up for the Stretch and Mobility series, but in the meantime I'm using P90X YogaX and Xstretch. I am trying out this schedule this week. Wake for 5 am workouts:
M - F1@60min
T - F1@60min
W - Xstretch + H1
Th - F1@60min
F - F1@60min
S - run/jog a mile or two + H1
Sun - YogaX + H1
I will replace the P90X stretch videos with GB Stretch series as I progressively purchase them. I'll probably keep the run on Saturdays and just add the extra GB stretch to that day since I should have extra time on Sat to keep the run since it's the weekend. I think it was during the Tim Ferriss podcast where Coach Sommer said running was OK, and even desired if you're over 40; howerver, it could have been on the Q&A audio that came with F1. To me, this seems optimal because it incorporates daily dedication and consistency, full body F1 exercises 4x week, stretching/mobility, and some cardio/movement, which I feel is in the spirit of the GB philosophy.
I know H2 is a core-requisite, but I figure I'll just move on to that and replace H1 after I've mastered H1 and have solid fundamentals. I'll put in F2 when I get there where F1 is. I have no idea where to put Mobility or how many times a week it is to be implemented; however, say it is to be used once a week, I would probably replace the run with Mobility since it seems cardiovascular in nature and I'll have more time on Saturday. I'll learn more about that bridge when I get to it (see what I did there).
The question of how to program GB has been been somewhat confusing for me too, especially when you can't really look at programs you don't own to see how the jigsaw puzzle fits together. From what I can tell from reading on here, it's something every person kind of needs to patchwork together on his/her own. If there are standard work schedules on here, I've missed them, and I apologize. The above is what I'm starting with and will adjust as necessary.
Please excuse typos and grammatical errors. I'm typing this on my phone.