For now, just keep them.
They would've been moved for AD, but at the moment, the Celts should just focus on free agency.
Reassess in the summer of 2020 depending on what type of season they've had and the overall state of the team.
The only wrinkle is Jaylen Brown is going to be a restricted free agent in 2020. So, do you commit decent sized dollars to keep him or do you deal him, possibly by the February trade deadline, depending on his value and who's available?
Anyway, I think until at least February, both guys stay in Boston.