We, you and I plus sombody else, I dont remember, tried this over and over and the conclusion was that it doesnt matter which settings we´d use, IL-2 is just cocked up when dropping bombs on stuff.
Well, we used mixed stuff back then... I was on stock 4.12.2m, (a really a separate install) while yours (and others) were using the Hsfx-installl with stock selected in JSGME.
Yesterday, before the briefings, Jabo, Fenrir and me did some more testing, and with both true 4.12.2m stock, and with Hsfx with History and Expert, the issue did not occur... As long as we all had the exact same install, and same (limited) mods activated, all appeared to be fine.