I asked around and here’s how this works. We require that you change your password every six months. As that time approaches, we start sending you annoying messages reminding you to change your password. The easiest way to avoid getting these annoying messages during non-busy times is to figure out when the non-busy times are (do they exist?) and change your password six months in advance of that, ideally during a time that is also not busy, since that will also be a time when we will send you annoying reminders to change your password.

Here’s what the schedule would look like:

June December
July Jan
August Feb
Sept Mar
Oct Apr
Nov May

I would guess that an early August/Feb schedule would be the best; thus, if you make a reminder to yourself to change your password in early August, then we’ll nag you again in Feb, and then again in August, and so on.