In colloquial speech, it is supplanted now by по + dative (e.g. «по возвращению в деревню»),
Couldn't you also argue that it can be supplanted by после + genitive? (e.g. «после возвращения в деревню», "after returning to the village")

In any case, here's another familiar example of по + prepositional:

Цыплят по осени считают!

Literally, "[They] count the baby chicks after autumn." -- i.e., "Don't count your chickens before they've hatched."

Here, осени is prepositional sg. and цыплят is animate accusative pl.