Hi Fujiabound and Twizzle,
Few points.
The additional training for tailwheel; wobbly prop etc is not for the grant of an initial licence so no problem there.
Point re differences between PT and Pvt C of A has some validity but you may consider that many mounts are on a Pvt C of A to avoid the need to have a new engine at TBO.
Even if all is complied with and no additional changes have to be made to the hardware a change commands a fee of the CAA. Believe that you do well if you get any change out of half a grand.
Frank