Early January is not really that bad, remember the league is starting at 22th of December, so that is like maybe missing only 2 weeks of games. Plus this season is shortened, and Celtics can make it to playoffs even without Kemba anyway.
Celtics caliber can work it out, they still have scorers who can fill that gap while Walker is still in bench. He can take all the rest that he needs to get a better shape when he's already available to playback.
So they need him to play a bit before the playoffs in order to get into shape and have match fitness, when he has that, he should be ready to go, like 20 regular games + playoffs from Kemba would be more than enough.
It's needed to blend him up to his team mates before moving to another round, adjustment is in need being done, and aside from that he's physical and mental condition needs being well prepared once he's availability already been approve.
However I should warn that this year will be teams going back and forth between their courts, instead of just staying in a bubble, which sounds very risky. We may hear about a lot of teams getting covid infection, at least one or maybe even more players could get it, and if that happens in playoffs that could change soooo much of the situation, I fear it could even be the deciding factor for the champions if things go wrong.
This risk is very possible, travelling the normal way would bring risk to each people not just the players but the team as whole might be infected of the virus. Strict compliance of all protocols needs being applied to any involve people from this league.
