They will be replaced, discussion is what with. Some favor a modified, smaller version of SVALBARD, some favor more BARENTSHAV hulls, and some again want something completely new (and expensive).
Since they just spend millions repairing ANDENES after her little crash and her recent deployment to RECSYR, I personally doubt she'll go into the buoys any time soon...
Yes since they repaired Andenes, she would be in service for an longer time, that means that the project for a new vessel is delayed.
Norway would most likely go for either an enlarged and modified "Barentshav class" with ice strengthened hull. or an totally new vessel that is capable to operation in all weather, with an ice strengthened bow, just like Nordkapp class.
I believe it would be an vessel that can replace and take over all task Nordkapp class have today, and it would be an vessel capable to operate comfertable in the North sea, but at the same time have some ice-breaking capability (not so extreme as Svalbard class). specially when we think about that today the Coast Guard are holding an close aye on Russian Navy, controlling fishing boats, transporting equipment for people all over in the North but also help out science people in the artice (Svalbard class have dad as it's main task, today)
Edit: done some cheeking, the new vessel, will replace "KV Andenes" directly, build with the same Principe. Government say the ship will have no weapons, but I think it will have. I believe it's a way for the Navy to tell its government, that the ship will have no weapon. then just a week later, the Navy equip it... behind the back of the government. Basically The Navy is playing poker with the government...