where an appeal against the decision has been made to the tribunal and the appeal has not been withdrawn, or the tribunal has already determined that matter, or
pan fydd apêl yn erbyn y penderfyniad wedi'i gyflwyno i’r tribiwnlys ac nad yw’r apêl wedi ei thynnu'n ôl, neu mae’r tribiwnlys eisoes wedi penderfynu ar y mater hwnnw, neu