HU Blinds are 250/500 ($5)

[DMMx69]

i dont think this makes sense. id rather check and see a flop with 10+ BB HU. 87s doesnt play that well HU.

SAGE recommends jamming with 87s only if the short stack has 6BB or less.

I see the mixup with BB/SB. In this case id probably just fold, although if the BB is weak/passive, maybe you can call BB.