According to Celtics wire and maxwell #11 jersey was available to rookies
This seems odds to me (though I've read it too). So with primo numbers like 4, 8, 11 available, Carsen Edwards willingly choose #29 (he wore #3 in high school and college)? Maybe there was some miscommunication and they were told #11 would likely be available later and that they could change their number before the season?
If you want the deep Celtics rumors, well it seems like Grant Williams has his eye on somebody else's number if you read between the lines on this tweet from him:
Hello to everyone who has asked or is thinking about purchasing my jersey. It is not certain i will be wearing number 40 this season however i will be wearing the number 40 for summer league play. Thank you so much!! #GoCeltics 💚☘️💚☘️
He wore #2 in high school and college which isn't available, but 9, 11, 12, 13, 30, 42, 50 which were all taken last season may become available this summer (some more likely than others).
Grant Williams already causing problems in the Celtics locker room