When does Trust Distribute to Beneficiaries?

I think I read that UBOT trust accounts have to payout excess funds (interest) once a year - it is setup as a UBOT, right? Operating Sovereign 2.0 suggests this.

Does the beneficiary get a check once a year or every so often or not until they are 25 or how does that work?  How does the payout get paid – what instrument(s) is/are used?  Is there a check system that can be ordered (such as magnetic account # style printed checks) or do I write hand-written documents or on white paper or ….. ?