I once worked for Medical Portfolio Ltd, a subsidiary of ICL based in Tipton. In deference to the ICL system of naming their buildings with the first three letters of the location and a sequence number, we called the building TIP01. Anyhoo, ICL brought us in-house, in one of the Birmingham buildings. After a while, the pathology system that I was the sole support for was quietly dropped from the product line, and I was quietly dropped from the staff. ICL paid a couple of guys at Hallamshire hospital IT department to maintain the system - their programming experience was from writing Spectrum BASIC. The consequences were not good.
https://www.theguardian.com/uk/2001/sep/14/martinwainwright
https://www.ranker.com/list/actual-y2k-failures/tracey-graham
Note: these are ascribed to Y2K errors, which they weren't. The dickheads who did the support didn't use the inbuilt routines to change date to day number and day number to date, but did something stupid instead.