Contacts at 10-14 days, 6 weeks and 6 months were prioritised in Welsh Government guidance issued at various times during the waves of the pandemic.
Cafodd cysylltiadau 10 i 14 diwrnod, 6 wythnos a 6 mis eu blaenoriaethu yng nghanllawiau Llywodraeth Cymru a gyhoeddwyd ar wahanol adegau yn ystod tonnau'r pandemig.