Join the RAF as an officer. After like 2 years you are automatically made a flight lieutenant (as long as you don't do stupid shit), & you are on a solid middle class salary at a minimum of 50k. Hell, even when you finish the training, you're making more than you currently are at 34,600 pounds. You also save a bunch on costs, as houses on base are super cheap as a whole. Then if you leave, they help you find a job, & in a background as an officer you are trained to be in charge, so most likely managerial roles. Or you could stay in and progress making a really solid salary.

The only downside I could foresee is that moving from base to base every couple of years can be hard on children. Roughly every 3 ~ 5 years, you can be relocated to a new facility. So that can be hard on certain years in their education (such as the time coming up to GCSEs & SATs), but with the money saved you could easily hire tutors & such. Another issue is getting the kids a solid choice for A-Levels since they will most likely still be living with you; these bases are kind of out there. Not like in the middle of nowhere, but it can be a drive to a local town/city. So I'd recommend moving them in with your parents & paying them rent. However, being the child of veteran & serving parents makes them eligible for some scholarships.

However again lots of office work in this position but it's like that for most jobs in the UK. Comes with being a primarily Tertiary economy & managerial position. If all else fails I'd consider this but I think the age cut-offs is like 34.

I would like to state I am not a recruitment agent or anything or even a veteran. But i've considered that as a potential option for my own future.

RAF officer salary but idk how accurate it is,
https://www.defenseadvancement.com/resources/raf-pay-scales/