Ok, I want to take a crack at this. Now, everything I (think I) know I learned here. And any discussion of August is totally hypothetical. This may be impossible, but if I were going to attempt the impossible...
FIRST, you'll need the quickest transportation option you can get. I'm guessing that's something like Uber/Lyft.
Either scenario, if you can enter AK at 8 and DHS opens at 8 or 9, I'd be at AK as early as you can to be at the front of RD and hopefully be one of the first to make it to FOP. Afterward, hustle straight to DHS as fast as you can and try your luck.
If DHS opens at 9 and "Back-Up Groups" are lasting a while, that's your best chance. You'd need the Back-Up Groups to last a crazy long time with an 8 am opening.
In reality - Do you have more than one morning, so you can make one day AK EMH rope drop morning and the other DHS BG morning? The first thing I would do (and the first thing I did do when planning my Feb trip this year) is make FOP my A#1 FP priority and the key to my whole parks schedule. Is there a reason you aren't planning to FP FOP, or just thinking in case you can't get the FP?
Wiser heads can talk about FOP at closing time. And ultimately you may just have to choose one ride over the other. Or both rides over a MK rope drop or other morning plan.
Man, have I missed this thread! Thanks for giving me something fun to think about.