A bit simpler than that, all you need is a Seminar and a A of C, no need for an ATO as such. The Examiner could do training with you or you could go to an ATO to do it. With the experience stated I can see no reason why you would be restricted, that is simply like the old AFI to allow a FI to gain sufficient experience to judge when a student is capable of doing a first solo. Nowadays you can be remunerated on a PPl for flight instruction.There is a change to the Seminar requirement in the latest FCL amendment, it says Theoretical Refresher Training at an ATO, which may of course be a Seminar.