There is another flaw in your plan which maybe you decided to ignore because it does not fit in with your plans.
If there are guys out there who have been instructing for four years or more it should indicate a serious lack of opportunities to move on. I also know several very capable and fully qualified people who cannot wait to get out of instructing into something they regard as better.
Sadly for them the opportunity has not presented itself. Its nothing to do with lack of talent or keenness or networking but pure and simple lack of opportunity.
What I am suggesting is not to throw in your day job whether you love it or hate it but study and train while in employment.
Sorry but that's my two penny's worth!