From what I have learnt, you can teach refresher courses without any training except in the thing you are teaching. This assumes that the person you are training already holds a qualification in the subject. So you would help a qualified waxer enhance his or her skills but you wouldn't be teaching them from scratch.
To teach a course that then needs to be accredited by an insurance company, you need to have pttlls. This is according to BABTAC but you may find an insurance company that will accredit your course without pttls but your students may then be limited in who they can get insurance with.
There have also been instances in the past where therapists think they are insured only to find they're not so you need to be sure of your facts.
Vic x
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