You almost had it pegged. Paul may have taken it that was at first but not years later when they threw it in his face because they meant keeping some Levitical Laws not just courtesy when they penned it. Paul then had to get rid of such thinking entirely and not just put up with it as he did for a long time.
What scriptures are you referring to?
TD~
Its confusing cause they just referred to animals being strangled, then they go into the blood thing. I guess, if there's no surrounding context then it's assumed it means literal blood?