Service Car No1 in LNWRstyle livery Kensington Olympia 1990s

Can someone throw light on this group of carriages? Although the LNWR & LNER liveries look good, there are modern features above and below the solebars. I am not sure of the date. I was visiting Olympia for a South London Warlords' annual 'Salute' wargaming event and I stopped going by 2000