So I've recently received the results to my ancestry dna test. It matched me with a woman who I shared 14% dna with, 997cMs across 24 segments, longest segment 113cM although I'm not sure if that will be any relevance to that and this post. Its placed us in the 1st cousin-2nd cousin category with 99% relationship being 1st cousin, Great-grandmother, Great-granddaughter, Grandaunt ,Grandniece,Half aunt, Half niece. We can cross out G.Grdm-G.Grdau due to ages, Grandaunt and niece crossed out as that would make her sibling to my grandfather which she is not. 1st cousin would mean her dad is my uncle, and she's very sure it would have been impossible for my dad to have had anymore siblings. So that leaves Half aunt.
Now I know my dad was adopted so this is a strong possibility when talking to this woman she has confirmed quite a few details that we were aware of but didn't have a name for. Was confirmed he was American, confirmed he was in military (navy) we know his biological mum was part of the WRENS so was the womens naval service so that does match up to them being on a naval base and did spend time in the UK around that time, did confirm he went to Vietnam which we knew.
However she has said his brother was military and also went to Vietnam but she's pretty sure he never came to the UK. We do match up to another woman who she has said is her dad's half brother which matches up to the possibility ancestry have given of maybe half grand aunt, however that would be the case either way as she was both brother's half sister.
So if her uncle was my dads biological father, that would make this match my first cousin once removed, ancestry haven't given this a possibility. Could ancestry have missed that possible relationship. From everything I'm reading 1st cousins once removed typically usually share 6.25%, would it be likely that sort of relationship could share 14%? I've read on average they share 433cMs but it can range from 102-980. Website I've used that calculate cMs like dna painter have said it would be 100% probabilities of the relationships that ancestry listed and none have listed the possibility of 1st cousin once removed.
So I'm guess at this very lengthy post (thanks if you read it to the end) is the chances of half aunt just more likely than first cousin once removed? Or should we still not exclude that possible relationship Many thanks