The CSAS panel, along with most of the cockpit, went through a few lighting changes. The original backlighting was rather dim under bright sunlight so the panel was redesigned with much brighter captions. With early NVG modifications some of these panels changed to a black background with illuminated green captions. Later NVG cockpits returned to the use of colour captions with appropriate filtering to remove the NVG-unfriendly wavelengths.
The GR4 update standardised most of the cockpit lighting again with NVG compatibility a key requirement. Of course, the frequent stirring around of LRUs and fleets-within-fleets made the cockpit lighting a bit of a lottery, especially in the mid to late 90's.
They never renamed the pre-flight test switch though, presumably through optimism.