While somewhat fleet/seat dependant, reserve tends to go a bit more senior here.

RSV is a possibility after being released to the line after training, or on a VTOR line (vacation/training/opentime/reserve, known elsewhere as a "buildup line")...very junior pilots tend to get VTOR lines or Base Trip Lines (BTLs have shorter trips, <110hr time away from base). If one has a BTL, trip trading with opentime can help manipulate your schedule some.