Unwritten law of pipe bands?

Today I heard about the P-M and L-D of a competing band resigning. Obviously, this happens frequently, but it rarely occurs after February.

I don’t know the circumstances yet, and I’m sure there are a multitude of reasons, but isn’t there an understood rule with pipers and drummers that you don’t leave a band after March? I always thought that no matter what you muddle through the competition season, and after the last contest bow out as gracefully as possible.

Has this ethic changed? Is it now okay to leave a band in a lurch?