I thought if you were forced to be a helper then you were paid as a driver. But if you volunteer to be a helper then you only get helper pay.
I could be wrong though.
As a seniority FT driver your guaranteed 8 hrs a day at your drivers rate of pay unless you agree to go home and take a dead day. Whether your sweeping the floor or working as a driver helper it doesn't matter. You should be getting driver pay.
The only time a Ft driver would get a different rate would be if they where laid off and where working back on the inside. Then they would get what would be there pt rate if they never went FT. That could differ by what area your in.