I currently have a job offer with big company B. The start date in the contract is due for 8 months from now. I'm thinking on accepting the offer, but I'm concerned about what would it happen, if for some reason I was unable to join them in the start date. I understand that it is a serious compromise and I don't want to give the wrong impression of being unloyal or unprofessional. As the waiting time is large, the concern comes from the possibility of having a personal/familiar issue in the mean time that could keep me from keeping the compromise of joining the company.
The job is in the UK and I'm not an european citizen. Of course I understand that if I find myself in that situation I would be closing doors and future opportunities, but, could it have any legal implications, such as being banned from the country (the company would sponsor a working visa) or prosecution of any kind (the company demanding some compensation for their recruiting time spent)?