How the fuck am I supposed to relocate when these are the 'rules'?

We moved about 2 hours away. Honestly, no one asked about jobs. 🤷🏻‍♀️ We had jobs. I was employed, Dh self-employed (well, company director). Our new house is about 2 hours drive from Dh’s business and 3.5 hours from my employer at the time. Didn’t make any difference to our mortgage. No one ever asked what we were planning to do about work. It was all based on affordability with our income on the day we applied.

I’d apply for a mortgage and interview for new roles for a September start. You may end up doing a crazy commute or living in temporary accommodation, but that’s fine.

I moved from London to Edinburgh, you get a job first by travelling for interview, then you give notice and sell your place, renting near the new job until the sale goes through. It's far far easier to buy and sell separately without a chain. You just need to factor in 3-6mo of rent to your costs. You are also in a much better place to choose the right property to buy once you know where your new job will be so a few months renting is worth it.

NHS will be hiring in a few weeks' time once the budget for next FY gets approved. I ended up relocating last time having found the job in early April and was ready for the new post in July. EA universally accepts contract in lieu of recent payslips so that wasn't an issue at all. But, as I said, much easier to find off season holiday lodge even if a tad more expensive than renting. You are not then competing with other renters which, in some areas, could be pretty fierce.
I think you need to let go of the idea that you will move from your current house into your new one right away. Once you make peace with it, you'll see that it's not at all hopeless.

People rent
Its not ideal, especially when there are so few rental properties BUT if you can get one you can give 2 months notice at any time (from May)
Having said that with no job its unlikely you will be able to do that either unless you offer a lump sum upfront. Agents can't sk you to do that (from May) but you can offer. However as you could still give 2 months notice and they would have to refund you Landlords will be reluctant to accept it, especially as there re probably applicants with secure jobs already who can pass Refrencing

It absolutely does! We have just employed a teacher who’s moving from London to Manchester. She got her job last month for a September start.

Actually, it just occurred to me that I have never moved without a job in place. So even renting wasn’t an issue.

Don’t school jobs tend to hire in advance of the next school year? It seems like that would make this easier.

Buy somewhere small out right then upsize after a year. Bonus points if you buy something you can add value.

We lied. Said we were living with our parents down south for free during the week and spending weekends at our new home. Worked, they're not there to question life styles only finances. Obviously when it went through we handed notices in and took new jobs up with new house.

Most people find the job first and then move to the job, renting, lodging or airbnb’ing until they have the stability to get a mortgage.

But if I was going to move 200 miles, I’d do it with my current job as they have offices around the country so I’d be able to work out of a local office immediately with some travel back to my current location and then I’d move to a more local role once I had actually moved,

I've done something similar and stayed in a holiday lodge off season for much lower rates and with a very flexible contract. I'd say your only options are to rent/lodge/stay in a guest house/property guardianship for 3-6 months, Keep your cash in a high interest ISA and savings account, then pull all your resources together when you are actually mortgageable again.

I’m with the mortgage companies. They only care that you can pay the mortgage and how can you prove that if you don’t have a job? It would be irresponsible to lend you anything.
Sell. Rent. Then buy at your leisure.

Can’t you rent when your first relocate and then buy once you have a job?

As in a temporary rental / longer term Air BnB. Or if by yourself you can find a share as you won’t need a job.

Usual sequence is

1. find job
2. find temporary accommodation
3. find permanent accommodation

If you have deep pockets, you might be able to skip a step or two. But trying to go straight to (3) is both difficult and risky. So even the very well off wouldn't normally go straight to that option.

Depending on your family situation, you might be able to rent somewhere small or even single room lodging for just one working adult while the family stays in your current home?

You might struggle to rent. In many areas there is competition for rental properties and landlords would choose someone with a job over someone without.

Being a lodger might be an easier, and cheaper, first step. Then get a job and then buy. You will also then be an attractive buyer as you are not in a chain.

When we have moved cities we rented for 6 months or a year and then bought a home.

We moved to North Yorkshire from London. We rented until we had both got settled work-wise and also had a chance to look at different areas to make sure we were choosing somewhere that suited us. Better that than buying somewhere and discovering that either the village was dead or full of unwelcoming cliques.