Not really, but it might not be even on the last mains.
On two piece jobs, both sides of the mains should tie off at same coresponding tie-offs, i.e. 7B(T) on both sides. Let say you you have two tie offs per side, i.e. 7B and 9B, and you use 9B on both sides, and tie off the cross at 7B, that's OK. Even if 7B was the designated tie off for the mains.
Machines: Gamma 6004 2-point w/ Wise 2086 & Babolat Sensor Dual