It has always been a mystery to me as to what sums the Inland Revenue would perform for one, if one were to submit one's tax return by 30th Sept.. Nothing on the return says "you may stop here, if you wish the revenue to do the rest of the calculation for you".
Anybody have any ideas about this, or even personal experience? ( I'm particularly intersted in the main form and the capital gains one, especially the latter given the imponderability thereof).
Is this a stupid question, by the way?