Yes.
I was just browsing the winter 1964 Victoria Carriage Workings - on the Chatham side there were a few 10Hap (splitting en route) but to my surprise on the Central side the 1736 Brighton was formed 12Hap. Surprise because I didn't associate Haps with the Central at all back then.
From a similar era and going back to an earlier generation of unit, I can find a number of 12BIL (6 x 2BIL) workings in the 1967 post-Bournemouth-electrification Waterloo CWN (available on the BR Coaching Stock groups.io group).
These include, in the evening peak:
1726 Waterloo-Portsmouth Harbour
1750 Waterloo-Woking
1758 Waterloo-Alton, off 1626 Alton-Waterloo (4BIL from Alton, further 8BIL attached Farnham)
and in the morning:
0726 Alton-Waterloo, forms 0857 Alton out (down to Alton as 12BIL, then up to Farnham on 1026 as 12BIL; 8BIL detached Farnham)
0810 Haslemere-Waterloo
I can also find another 12HAP to add to the two above, which worked as a 12HAP through its entire journey, thus beating the two above for mileage:
0656 Portsmouth Harbour-Waterloo
1967 on the SWML was clearly where it was at for 6-unit workings! There are also 10BIL and 10HAP workings, too.