The straight answer is no. The pot taper will only affect knob setting, not tone in any way with all other things being equal. That is, same bright circuit, pickups, tone pot/cap value, etc. Which means all other things aren't equal. Now you get to find out what. I'll guess it's the pickups may be somehow different than typical and their particular resonant properties aren't playing nice with the 250k pot value. I might try changing to 500k pots and half the value of the tone cap and your usual bright cap.