Workplace Home to Office Mileage

Hi there, I'm trying to gain some understanding on tax free business mileage. I have just started a new job, my contact states the head office in Exeter is my perm place of work, however I am on a 6 month probation and only go to the office under the 40% rule. I live 300 miles away from the office, and the company say I cannot claim business mileage @ 45p rate as its ordinary commuting. Do I need my contract to state I am employed remotely from home and also does the 6 month probation that's there, mean that in theory my particular place of working as under 40% is temporary?

Hi ,
 

This would be seen as ordinary commuting and yes you would need to have your employer change the place of work - that may happen after your probation ends. The fact that you are under probation does make it a temporary workplace . Thank you .