I'd disagree with Fuji on this one... I'd also be interested to hear what other think.
What is not allowed is "instruction in flying given for the purpose of becoming qualified for the grant of a pilot's licence or the inclusion or variation of any rating in a licence." (My highlights, to indicate the bit which could, possibly, preclude twizzle's situation.)
A tailwheel checkout is not, as far as I'm aware, a rating (which would need to be explicitly listed on your license) nor a variation of a rating (not sure what that would be - maybe a night qualification, which, although not actually a rating, does get written onto your license?) It is a requirement, but the requirement is satisfied once you've had the training, there's no need to have your license updated.
It's also worth noting that, under the PFA coaching scheme, a PFA instructor will train you on your PFA aircraft, including any complex checkouts (including tail-wheel) which are needed.
And, from a purely logical point of view (although we all know logic has very little influence on these things!) it simply doesn't make sense to not allow someone to do a type conversion on the type they're converting to!
FFF
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