I echo tropical, solo sign-off is a PITA. You spend much of your time doing Ex3, eventually you'll be trusted with a couple of students. You may even get them to the mid-12/13s but then someone else will have to take them for first solo. If you're lucky, you may get a couple of consolidation sign-offs and then some solo navs (qual x country only counts as one!). All the time you're probably not being supervised very much/at all, the most difficult lessons to teach (4-9) are often thrown your way and nobody cares; you are low life.
There is a school of thought that solo sign-off should actually be solo (non) sign-offs. some of the more difficult decision you will make are those when you decide NOT to send someone solo. The system sucks, rarely does it actually make one a better instructor (due to the actual lack of supervision), most clubs/schools look upon you as a costly (!) inconvenience and it does nothing to encourage individuals.
(CGB, unrestricted after 420hrs instruction over 13 months
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