A messenger is tasked by a nobleman with delivering a message to one of his peers from Byzantium to Ancyra, and returning to Byzantium with a response.
The message is of some importance, but not a matter of life and death.
Assuming the messenger spends no more than one night in Ancyra, how long could one reasonably expect the round trip take?
Note: I am unsure whether messengers in this era would have travelled on foot or on horseback, which further complicates matters.