I could be wrong (I often am) but I could have sworn an opponent who's spent most of the last month on vacation was down to a day or two left of his allocation. All of a sudden, he had exactly one month left. How could this happen? Or am I just going madder?

Did he recently upgraded his membership?  That's all I can come up with... I know you get more vacation days with an upgrade.

It might count as cheating.