They can't place you on a contract that would go past the visa expiry date, the fact you will apply for ILR and almost certainly get it is irrelevant, to them you may not. So they would only be able to give a temp contract.
My wife got a job after 1 year here, so another year to ILR, they put her on a short term contract but with an agreement this was extendable. When it was time for her ILR they requested proof that she had applied (she gave them a copy of the letter to say the application had been received), so that was acceptable to extend the contract but they needed proof of the ILR as soon as it was received.
It may also depend on the size of the company - this is a big bank, so they actually have a department within HR that deals specifically with foreign nationals being employed so they are on the ball with regards immigration legislation.