Solo with expired class rating?
To set the scene; I'm doing a type/tailwheel check-out for an ATPL(UK) who's buying a share of a SEP tailwheel aeroplane.
His SEP class rating has expired about 8 years, so before doing the renewal LST he wants to complete the tailwheel differences training and revise for the test.
My question is - Can I send him solo for a bit of extra practice under the privilege of my FI (unlicensed field).
My interpretation of Article 21(b) is "yes I can"; but as its a relatively unusual situation, I'd like to consult the oracles.
I would, of course, sign off the differences training prior to doing so.