I’m still none the wiser if BF offer both 4 and 8 ohm alternatives on all their cabs. Some manufacturers do. It’s not an unreasonable question.
I just took it for granted your 112’s were 4ohm or at least one of them was as you’ve talked a lot about your ‘900w at 4ohm’ - it’s no biggie just could be misleading for folk who were reading along. Actually it’s one of the reasons I was unsure if BF offered 4ohm versions of their 112 cabs as your statement implied (to me at least) you were getting 900w from the BB2/AO900 pairing. Most folk would discuss their gear in real terms - output etc. An example one of my amps is capable of 1200w but I don’t run it at 2ohm - I generally talk about it as an 800w at 4ohm head as that’s how I use it day to day.
But you’re never taking two cabs to a gig 😀