Poole's temporary rider until end of June is Matt Marson   https://www.poole-speedway.com/news/view/20250120-marson-joins-starting-seven    

Harris himself gave a statement in October saying he wasn’t in Oxford’s plans and didn’t seem to be exactly pleased about it either.    https://watch.britishspeedway.co.uk/articles/bombed-out

True but surely the club they are riding for should have first refusal so maybe Harris decided he did not want to ride for Oxford anymore.

He'll put the wind up the opposition.