The vile pale blue cummerbund was standard for a while, then blue waistcoats were allowed to be worn again. Most real squadrons had their own cummerbunds, but then 'They' decided that we all had to look the same - so blue waistcoats became mandatory again (without any re-kitting allowance, of course)...
...or so 'They' expected. But the rule was given a stiff ignoring, as most real squadrons decided that individualism was preferable and to hell with the consequences - if the PMC expected anyone to volunteer for Dining-In Nights, that is.
I've just found that duck egg blue Alkit thing and what a dreadful piece of rubbish it truly was. The gaudy red-and-white chequered cummerbund our 56(F) spam exchange officer's wife made looks so much smarter! As does my 101 Sqn cummerbund and tie.
But I haven't been to a formal dinner for a few years now - in any case, DJ and mess kit trousers shrink when left unworn in a wardrobe, it seems!