If 11.3 is mirrored based upon season, it is 42 days after the autumnal equinox which then is 42 days after the spring equinox = 5.1 = May day
English historian Ronald Hutton concurs with Swedish scholar Carl Wilhelm von Sydow who stated that maypoles were erected "simply" as "signs that the happy season of warmth and comfort had returned."
https://en.wikipedia.org/wiki/Maypole