No it isn't.
Last year, I was speaking to a Foreman who had just left the mob and he told me the same thing.
He was fairly young for a WO so I asked him why he was quitting and this was one of the reasons.
He didn't mention anything about time limits but he did explain how a recruit can pull the yellow card, show it full on in the NCO's face and say words to the effect of "You are stressing me" and the NCO has to tread very gingerly from then on.
I think i've cracked it, it's amazing what's in hansard
On the question of red and yellow cards, reports of which appeared in the newspapers, it is true that recruits were issued with temporary identity cards--I stress that they were ID cards--while they were waiting for permanent documentation at two Army training centres, one of which was at Glencorse in Scotland and the other at Lichfield. The cards were indeed red and yellow, but they were for the purposes of aiding staff in the NAAFI. The cards made it clear who could and who could not be sold alcohol. For your Lordships' further elucidation, I add that in Glencorse the over-18s were issued with yellow cards and the under-18s with red cards. Your Lordships will not be surprised to learn that in Lichfield the exact opposite pertained--the over-18s had red cards and the under-18s had yellow cards.
Dear dear god please lets hope its not true!! I belive that millitry disapline is on a downturn, It does need to be pointed out that these young men and women are being trained to take orders under fire or steam valve conditions, strangly enough I dont think that the bloke with an AK in your face would be too bothered about the colour of the card in front of him right before he blows there head off! I think an old trg sgt hit the nail on the head when he said:
'You cant train a rockweliler to rip out the throat of an intruder one moment and then lick your baby's face the next!'
It is worth noting how that many other nations armed forces admair the reputaion of the screaming CSM. I use this next example dubulsy but the TV program "Bad Lads Army" and such sorts with children on chat shows i.e. Trisha where problem kids are sent off with that bloke whos name I cant spell! The bad lads army has shown a dramatic improvment in the partispants, why? Because it has given these guys a sence of acchivment and pride!! I know there are problems with recuitment and retention and by no means do i belive in bullpoo for bullpoo's sake! But is the anwser in dwindling numbers to plug the gaps with sub-adiquate soldiers who arnt really bothered about what their doing but just when payday is!!
The only red cards I've seen are the local issue ITD(A)10 immunity card, which when shown to recruits think it's true 'cos it's got a JSP number etc on it. it lasts until about the time they get the equal Ops & diveversity lessons off of the RSM.