Okay, looking at this since hopefully we’ll get this darned move done early next year this just doesn’t make sense since we’re both pensioners so how can one have to pay while the other “non employed” doesn’t? Neither of us will be working. 
Tbh I’m tempted to just ignore Swiss health insurance side except I don’t know what would happen when I stop paying the premiums. UK we’re already set up with a GP and they’re quite happy to treat us for free; didn’t even need to provide the paperwork suggested here.
Can’t remember if we did that form or not when we registered, but they’re happy with what they have on us including our NHS numbers.
And this contradicts that we need to continue to pay Swiss health insurance premiums.
" Returning to the UK to settle
UK citizens who return to the UK on a settled basis will be considered as ordinarily resident and will be eligible for free NHS care immediately."