Items Pending Changes

[Loki]

Do items that get buffed have to be re-obtained? I know that for nerfs, there are nerfed and pre-nerfed versions of items usually. But what about when an item gets improved?

An example of this is the Burning Rapier. I am working on that quest now but I want to know if I should do the final step or not. If I complete the quest and I get the pre-buffed reward, will that item in my inventory become the buffed one later? Or would I need to do the entire quest all over again?

My apologies if this was asked and answered elsewhere. I searched but could not find it.

Thanks!