Recently release sequences (at GISAID) provide compelling evidence that the UK variant is rapidly evolving via recombination.  An isolate from Scotland (hCoV-19/Scotland/CVR6032/2020) has 8 of the 10 Spike mutations - it is missing the 6 BP deletion that encodes H69 and V70.  Moreover, it is missing the 9 BP deletion in NSB 6.  The presence and absence of these well established deletions in the UK variants is most easily explained by rapid recombination.

Another isolate from Scotland (hCoV-19/Scotland/CVR5974/2020) has the same constellation (the common 7 Spike non-synonymous changes and the Y145 deletion but no deletion of position 69/70 and no deletion in NSB 6.

Same constellation for hCoV-19/Scotland/CVR6031/2020