Thanks for that Genghis, most useful. In my case AIUI he can renew his microlight class rating anytime before actually applying for his SSEA class rating. I'll check if his differences training on 3-axis was signed off when I see his logbook, if not I think I can do it on SEP under part c(3) of the cross-crediting document.
BEagle, I wasn't meaning to be particularly critical of NPPL and the cross-crediting allowances. I believe they are generally sensible and realistic, but are also minimum requirements. I really appreciate having the NPPL and associated ratings as an option for customers, who may otherwise have given up or not bothered with flying in the first place.