About 8 years ago when I was last consolidating, the schedulers told me to submit PDO bump requests while on reserve after 10 a.m. the day prior after they have made the sick call assignments for the next day. A call to the scheduler beforehand to explain is not a bad idea.
Also, talk to the person you want to bump. Don't just submit a bump without the other person knowing about it. Have had that happen twice. Usually people will gladly get bumped. However, that person may be on that trip for a specific reason (visiting family, friends, wedding etc.). If it's a deadhead, that person may need the bank money to cover deficits elsewhere. Doesn't do commuters without a crashpad any good to get stuck in domicile midweek for a day.