well that leaves us with figuring out which of the two times it was put into reserve they mean.
The german wiki-article writes that the voyage it undertook after being decomissioned and placed into reserve (which the EN one calls recomissioning) was a yearly summer-trip of the reserve-fleet…
So I assume it’s gonna be February 25th then?
Although when you take the “quarter of the month the day is in” approach, you get Q4, which would not work when you consider that you have to invert the number, since that’d get you 04 → 40 or 4 → 4, neither of which work.
If you take the “quarter of the year the month is in” approach then you get Q1 and as such 01 → 10 as possible answer.
(and as such 10-08-2026)