You still can update it though, download any variant of the new update via Navifirm.exe, if you haven't used it before, Navifirm is a really useful program that downloads all firmwares of NOKIA phones from separate servers other than NOKIA's one(s). The real good thing is that you can select any variant you wish, which solves the problem of several languages disappearing after an NSU or OTA update. Flash the image with JAF, the mass storage remains intact but all of the C drive is wiped.
You can as well reflash one of the many rocking cooked FWs out there, I recommend HyperX's one.

There are many tutorials out there, but I may give you one if you wish.