Hello,
I am not sure what the fastest you could shut down the BOM with no oob is, but if you are doing an IL run and not counting the time to get blueprints, then you probably would want to give yourself 12 or 13 minutes to be safe as it is very difficult to shut down the BOM in under 11 minutes glitchless.
Also, are you allowing going through walls/doors/etc. that don’t go OOB? If that is the case, if you’re doing a full any% run, you would not be able to get into helm without having 100 GB’s (or 80 GB’s if you do the b lower glitch). And if you’re getting that many GB’s, you would want to get a lot of blueprints anyway.
If you have any more questions, feel free to join the DK64 discord. There’s a lot of people on there who would be able to answer any questions you have. https://discord.gg/0SFjSv4JkQcMRidH