It shouldn't need bias reset unless there is a component changed. I have not needed to re-bias my VT 200 except when a tube shorted causing a resistor and the power tube to need replacement along with one of the 6922's.
I believe the replacement cycle recommended is 2500 hours but the amps do not have hour meters so unless you keep track of playing time, it will likely be an estimate anyway. It never hurts to check the bias but be careful to follow safety recommendations and don't do it yourself unless you are trained in electronics.
Follow the owner's manual on recommended maintenance or call ARC. They are very helpful with customer service to ARC owners (or to anyone for that matter).
I believe the replacement cycle recommended is 2500 hours but the amps do not have hour meters so unless you keep track of playing time, it will likely be an estimate anyway. It never hurts to check the bias but be careful to follow safety recommendations and don't do it yourself unless you are trained in electronics.
Follow the owner's manual on recommended maintenance or call ARC. They are very helpful with customer service to ARC owners (or to anyone for that matter).