Well either memories are fading or something is wrong with those dates on H.E.
I have spoken to several lads now who went down south with 2 and 3 PARA and all agree it was the 2" mortar that was taken not the later 51".
But they all independantly stated it was only H.E. taken with them and if they wanted PARA ILLUM or SMOKE the Mortars Platoon would provide cover, as the lads tabbing had enough to carry already, with link etc