Can I upgrade my wallet in the future, like 1-2 years from today?
I am a long term holder, I've been holding for over 6 months, I have not open since the day I created it and added bitcore funds to it. I only check my balance when needed via
https://chainz.cryptoid.info/btx/ knowing it's still there

and recently I checked my converted address since the old address is empty.
Thanks all in advance

That should not be a problem, but this is important update so it would be wise to see that you actually made to convert your old address while this subject is fresh and you have someone to ask if you run into problems.