make the claim within 4 years beginning with the day after the filing date for the tax return to which the payment by way of devolved tax, or the assessment or determination, relates
gwneud yr hawliad o fewn pedair blynedd sy’n dechrau â’r diwrnod ar ôl dyddiad ffeilio’r ffurflen dreth y mae’r taliad ar ffurf treth ddatganoledig, neu’r asesiad neu’r dyfarniad, yn ymwneud â hi