You want to consider to modify the powervalve after every rebore just out of precaution. But 2.00mm is when you need to modify the valve. It's a natural thing on all two strokes to modify the valves.
But as Cal says you atleast want to check clearances on the powervalve for every rebore. no 2 valves, bores or pistons will be exactly the same. If you're not sure then best get the company doing the rebore to mod the valve and check clearances too. That way it will be quality work and should you have an issue you can go back to them. I'll be sending a 350 crank, 125 crank and barrels from both off to pjme soon as both here and the 350 forum all reccomend them.
