DO I HAVE TO WORRY ABOUT MY NEW TRV?

[Laulau]

I am planing to apply for an extension of my study permit soon and I will probably not get it before all my documents have expired (TRV and study permit expires in one month from now)

Next, do I have to apply for a new TRV or an extension of the current TRV after I get my study permit extended?
In any case can I continue going to university while I wait for a new TRV with a valid/new study permit?

Thank you