Pellets are convenient but that is all they have going for them. T7 is very dirty, pellets are very inconsistent, and it is pretty corrosive and leaves a ring of hard crusty burnt sugar at the ignition location that is really difficult to deal with in the field. Bunches and bunches of deer have been killed with T7, including 30+ by me and my son but that was the best option at the time, it just isn't today.
BH 209, more efficient burn, better energy performance per grain, very consistent, way less fouling, far less corrosive.. Costs more and isn't available in pellet form( that is a good thing).
If you don't have time to make the switch this year kill your deer with T7, it will do the job for sure, but do yourself and your gun a favor and switch for next year.