Question: how does tdy per diem work?
Answer: Long-term TDY is any temporary duty longer than 30 days. Travel from 31 to 180 days will receive a flat-rate per diem of 75 percent. For travel greater than 180 days, the flat-rate per diem will be at 55 percent. Flat rate will apply to all three parts of the per diem - lodging, meals and incidentals.