These are all good ideas, but as macdo alludes to, they all take time. I actually looked at surveying a few years ago, as something to work towards in spare time and maybe do as well as flying. It’s a minimum 12 month course (double that if you distance learn), to get to the entry level standard (a way off £40k p.a. too). I can imagine how the conversation goes - “Hello bank manager, I’d like to take a 12 month mortgage holiday to spend 10 grand on a course that might get me a job earning half my old salary maybe.”
It’s crap. All these ideas are good for is long term planning, 2-5 years to get back to a reasonable middle class existence (and nowhere near our previous lifestyles). It’s going to be an absolute bunfight over the next 18 months just to keep the lights on.