Can I switch jobs while the tier1 extension is still on?

[random.thoughts]

Guys,
My visa expired on 1st Oct 2012 and I applied on the 12th of July. I have now got a very good job offer and I have marked the joining date to be 7th Jan 2013.

I am hoping that my visa will arrive before that however I would like to clarify the following.

1) Am I eligible to work/switch jobs when my decision is still under consideration? What would I be telling my new employer if he asks visa on day 1?
2) Can I state this as a reason for expedition? Would that be acceptable?

Are there any legal guidelines someone could point me to?

[geriatrix]

1. Why not, if the employer agrees to recruit you on the basis of an acknowledgement letter or, if they can make the effort, on UKBA's response to employer checking service.
2. No. No.

Legal guidelines about what?

[goldfish]

As sushdmehta says, you can change jobs while your application is in progress. However, a new employer is likely to be reluctant to employ you because (from their perspective) you may be rejected and have to stop working, and they will have invested time and effort in training you without getting the benefit.

An existing employer is more likely to keep you employed while waiting for the visa because you already know the job, so the "worst case" scenario is that you have to finish in a hurry if you are rejected. Sometimes even current employers are hesitant to keep someone employed while waiting for their visa.

I am surprised that your new employer didn't already ask for proof of your right to work, but if not then they are likely to ask for it before you start. You would have to explain the extension process, right to work while it is being processed, etc. You might want to have a discussion with them before your start date to avoid giving them a surprise on your first day.