Future Timeline

First, it will be the first Ash Wednesday to ever occur on a leap day in the Gregorian calendar. Second, it will be the first time since 1896 when one must wait eight years before the next leap day. Century years are not leap years unless they are divisible by 400, so the year 2000 was a leap year, but the year 2100 will not be.

So, we should celebrate both of these special occasions on February 29, 2096. Babies born then would then have their first birthday in 2104, and their birthday would not be on Ash Wednesday again until the year 2468 (which, well, consists of all four nonzero even digits).