Trump sentencing.

https://apnews.com/article/trump-hush-money-sentencing-e20933f9418bd378925e5f9e75f28485

As far as I know, the justice department is silent on the issue of whether a sitting president is immune from criminal proceedings that are not federal. Am I wrong about this? While it would be reasonable to assume that the argument they apply for the federal situation would apply in other situations, as far as I know that isn’t up to them and such a determination has never been made.

And therefore, why does the judge say that a sentencing does not happen before the inauguration then it would need to be postponed until after the presidency? Is that just as a courtesy or as an assumption that the justice department position if adjudicated at the state level would be concurred?