This isn`t really a reply, just something that I noticed. I am not criticizing your knowledge or anything like that, I just thought you should know that the term "lightyear" is a unit of distance, it is the distance light travels in one year in a vacuum.

"If the light we receive as evidence of blackholes takes millions of lightyears to reach us how do we know they still exist?"

You used it here as a unit of time, I just wanted to let you know in case you were confused about the term.