It's always best to list for first class and have the upgrade with you. If coach is full, they have to clear the non-revs listed in First Class First, even if you are on a SA3 and and a Coach Non Rev is a SA1, the SA3 would get on first because you were listed in F/C !
Travelers should always list in the class of service (Coach or First Class/Envoy) in which they intend
to fly. Gate procedures dictate that non−revenue passengers are cleared in the order of boarding
priority on the standby list. Non−revs listed in First Class or Envoy can be cleared a Coach seat if
First Class or Envoy is not available, but non−revenue passengers listed in Coach cannot be cleared
in First Class or Envoy until non−revenue passengers already listed for First Class or Envoy have
been seated, his/her attire meets the dress code for First Class/Envoy, and they have purchased an
upgrade. Gate agents should not be asked or expected to clear non−revs to First Class or Envoy if
the criteria described above is not met.