Get everything in writing especially when it pertains to the following items :
Accomodation and the duration the company will pay for
Flight tickets
Living Allowance
Relocation expenses.
Or else you are going to be suffering in UK if they don't specify it in the contract and with a contract signed like that , you are incurring a huge economic loss for yourself with the addition of having sold ur soul for 3 years. And to get out of contracts , damn hard - repayment of bonds are hell .