All going well, I should be back on the road for the weekend so want to do the legal stuff - insurance and road fund tax as quickly as possible.

Car is on SORN.

If I get it insured Friday, will the computer system thingies be up to date so I can do the online tax thing on the same day or on Saturday?

Or failing that, go to Post Office - do I need my insurance document with me for taxing after being on SORN?

best to do it at a post office

you'll need the MOT & insurance docs, I also bring the log book along too incase there's any questions like engine size

usually seems to take 24 hours to get it onto the online database, however, they say up to 7 days usually. At the PO you need mot and insuance, so you would still have to wait for your cover note to arrive.

If you try to tax online and it hasnt been updated, they dont let you try again for 24 hours.

Best bet IMHO is insure it sooner, and if you can find your mot, do it in person at the PO.

Your best bet is to go to a brokers office where you can get a cover note there and then, thats what my grandpappy always does.