The Longman Dictionary has a sentence:
He spoke about that afternoon for days to come.
It struck me as odd, because it seems to me "for years/days to come" can only refer to time in the future. There's several other sentences on the same page:
Alice knew then that my father would haunt her for years to come.
The responsibility was going to haunt him for years to come.
These two sentences sound perfectly fine to me, because they both look into the future from a reference point in the past, whereas the first sentence "He spoke about that afternoon for days to come" is talking about an event that happened in the past. Is it grammatical and natural?