This has some info:
http://bitcoin.sipa.be/ver9-2k.png
CSV is check sequence verify, but that is already locked in, so doesn't appear.
BIP 91 is segwit2x (same bit anyway)
SegWit is raw segwit, it would need 95% to lock in.
If BIP-91 hits 80%, then SegWit signalling becomes mandatory, so it will go to 100% automatically, and then lock-in segwit mid-August.
But it's all the same segwit anyway. Even if segwit gets activated with BIP91, it's the same code and it's compatible with all clients, so we don't need to run the segwit2x crap to enjoy segwit.
After segwit is locked in a lot of miners will not support the hardfork. You are delusional if you think 80% of hashrate wants to hardfork in 5 months.