[codethief]

> a few days after the presently observed light was emitted) and we would never know it until it's just about too late.

Right, good point! I shouldn't have skipped my morning coffee.

> if it was hit by something big

For the record, I assume you mean not a literal "hit" but some sort of binary interaction with another very massive object that ends up transferring (a lot of) momentum to the black hole.