Docos House. Not heard that in a while, gave me the shivers. Ever Ready used to use them as a bureau (a form of computer AirBnB for our younger readers) to migrate weekly sales on LEO III tapes to IBM format. 
 
Docos House had a System 4 tape drive on their LEO III system. From memory it the LEO III/44 was mostly used for application development and testing. Only ever went there in the evening, so did they not work night shift?  While I would wait for some spare time on LEO III/44, Post Office work took precedence, I would go out to a local pub near Docos House for a drink and an iffy pie. It was 1970, hot food on the go in the evening came from a strange dingy brown glass cabinet behind the bar. It was the Commercial Road of 1970 too. Quite different from today. I was only a mere strapping 6ft 4 teenager and it scared the whatsits out of me to go into that local pub in the evening. The sort of blokes you would avoid at a football match; don’t look at anyone. But then I was only 17.
 
An alternative was at Charles House but that was mostly on night shift where live Post Office work was done. Corridors full of trolleys with telephone bills on them. Many hours waiting around for a spare moment to migrate the tapes. At least I don’t remember being too worried about food. It was the night shift so would stop to grab a Bendy Burger at the all-night Wimpey at Golders Green. Happy days.