I want to transfer/advance to a different department within my company. It is based in France but I currently work in the UK.

My employer is refusing to allow the transfer on the grounds that in France I would have to work shorter hours on account of the WTR. There is no opt-out as in the UK.

Is this a legal objection? Surely the WTR are there to protect workers? I am being denied new job opportunities because in the UK they can get me to work longer hours.

Can I not simply retract my opt-out within the UK? Any ideas how I can challenge their decision?
Daniel Neil