The interviews ranged in length from 10 minutes to 90 minutes, averaging 45 to 60 minutes, with the shortest interview being one where the person was still seeking immigration advice.
Mae canolrif yr amser aros yn amrywio o fis i fis, ond dros y 5 mlynedd diwethaf mae wedi tueddu i amrywio rhwng 4 munud 30 eiliad a 6 munud yng nghyswllt galwadau coch.