Ers i’r gwall ddod i’r fei, mae CThEM wedi bod yn gweithio gyda’r sefydliadau yr effeithiwyd arnynt, er mwyn cywiro’r mater. Mae CThEM wedi cadarnhau y bydd y gwall yn cael ei ddatrys cyn i gyflogresi mis Mai gael eu prosesu, ac y bydd unrhyw achosion o dalu gormod neu rhy ychydig o dreth yn cael eu cywiro bryd hynny.  O ganlyniad i hynny, ni fydd y gordaliad na’r tandaliad gan unrhyw unigolyn yn sylweddol.  Bydd unrhyw wall yn swm y dreth a dalwyd yn cael ei ddatrys drwy broses cysoni trethi safonol CThEM ar gyfer Talu wrth Ennill, ac ni fydd angen i drethdalwyr Cymru wneud dim. Ni fydd hyn yn effeithio o gwbl ar yr addasiad i’r grant bloc.
Since this error has come to light, HMRC has been working with the affected organisations to rectify the issue. HMRC has confirmed that the error will be resolved ahead of the processing of the payrolls for May, with any over or underpayments incorrectly applied in April being rectified at that point. As a result, there will be no substantial under or over payment of tax by any individuals. Any errors in the amount of tax paid will be resolved through HMRC’s standard tax reconciliation process for PAYE, and no action will need to be taken by Welsh taxpayers. There will be no effect on the block grant adjustment.