i am in a similar situation,though i have not done a thing about it because I KNOW there is nothing you can do, short of telling them that you are skipping the country, that will move the tax authorities faster. there are other factors that should also be taken into account like your employer filing their provisional company taxes/info etc which is the info that actually informs the tax office that you have earned more than 120kCHF.

it will never be too late to file a return, the issue you will have is how fast THEY deal with when you have made the return. when they ask for it you have to supply it. but you can usually get an extension on the time required to submit.

your second question: its not logical at all!

did you earn Gross (120kCHF * 7/12 =70kCHF) in 2007 in CH?

if so then you should have received a tax return to fill in, if not call into your local tax office and explain your situation and they will probably give you a form to state the situation, which will later trigger a request for a proper full 2007 return.

if you earned less than 70kCHF in CH then you will have to prove that you earned >120CHF a year worldwide and try and convince them that you should make a return. you would have to apply for a full rebate in the UK in that case. again that will be clear if you talk to your local tax office.