Back in the 90s when I was doing a lot of agency driving for Blakes out of Alcester, this was pretty routine. Set off at 4am (after a 3am start) and drive to London with first drop at Smithfield. After that, four or five drops all over London and a collection in Dagenham.
With a bit of luck, you could make it back by 7pm to Oxford MSA or even Cherwell, and they would send a driver in a van to run home. We got paid for all the hours and I think my b̶e̶s̶t̶ worst was 21. I would probably have been back in at 4am the next day too.
Post ‘Skills’ there was a clampdown and Blakes and a load of their drivers were heavily fined - I got away with it.