Technically the theory test could be passed in the morning and the practical take place in the afternoon. But it would be highly unlikely. I have had someone pass a theory test the day before a practical. ROG is correct in saying the test has to be cancelled 3 clear working days in advance. But that’s not the same as buying the test direct. As a test centre, we have our tests virtually guaranteed. We could, in theory, cancel a test on one day and obtain a refund on our prepaid fee. Because the examiner cant be deployed anywhere else, we can then buy the test again at very short notice.
But none of this is advisable and I would always recommend that the theory test is done and dusted before the practical is organised. To do the above is verging on an abuse of the system and this would inevitably cause bad feeling (at the very least) with DVSA. It’s not a path we’d want to pursue.
The advice given on looking for cancellation theory tests is sound and I would commend that to other newbies where it will relieve pressure.
Pete 