That Carlton endcap's very strange for something made in 1999/2000. The "X Programme for ITV" endcaps stopped after the ITV rebrand in 1998, but that still has the old ITV logo on it! There shouldn't even have been a Carlton endcap by this point, with or without an ITV logo.
In fairness CITV playout at the time would have cut it off so it wouldn't have been seen anyway. The VideoFTW clips are obviously not off-air recordings from that era.
Still seems unusual it was put on the show anyway at that point. Unless it had been made in 1998 but had been sitting on the shelf for 18 months-2 years.
Series 12 went out from January 2000 so that would have been filmed probably the previous summer, just about predating Carlton's shiny new 1999 package. In fact most series after Series 4 went out in January (Series 4 went out from October 1991, Series 5 from January 1993, Series 6 from February 1994).
But then of course CITV presentation always was the odd one out in ITV terms. Never adopted the 2001 credit look for its programmes, half-adopted the 2002/3/4 credit adaptions for a while and then decided sod this for a game of soldiers...