So, if I'm reading all this correctly, Seymour wasn't born a Hales i.e. not the son of Joseph Hales and wife Elizabeth who he is with in 1939 - one can only assume that for whatever reason he was adopted by them.
I'm assuming that since his birth parents are shown as Joseph Ernest Thacker (married to someone else) and Ada Mary Peace, nee Geere, widow) that his birth certificate has been purchased at some point.
That being so, then his bloodlines are Thacker and Geere (no Hales blood at all).
Annette