Going back to the initial question posed in the thread, yes for many years the grant was paid to help cover the difference in advance payment between the manual and automatic versions of the same vehicle.
However, nowadays in cases where there is no direct correlation between the manual and automatic versions of the ‘same vehicle’, Veterans UK are taking a more pragmatic view and using a ‘closest vehicle’ as the metric.
I know a piece of work is being put forward, via the Veterans Advisory & Pensions Committee (VAPC) for North East England this coming September regarding the future of the ‘automatic transmission allowance’ if, as or when the majority of vehicles on the scheme become solely automatic due to being battery powered.
There are several options being put forward by the VAPC to try to retain the allowance in some form (alongside the other WPMS grants for such as hoists, swivel seats, hand controls etc etc).