Cryptic

This is a calendar...

...that represents 9 days. Today, two of those rings are coming off.

The calendar started with 420 rings, conceptually, that is. It's has taken 2309 days to go 413 days, to get down to 7 remaining days.

I feel like this is one of those things where I should say, "Flash the secret sign if you know what I'm talking about."