On 9 Mar, 06:54, "IanMayo" wrote:

the upstairs lighting ring is off (no lights works), but the circuit
breaker covering that ring is still on

Your lights are on a ring?

Are _any_ of the breakers off? If so, then the lights might not be on
the circuit you expected (Anyone else with added en-suite shower-
rooms entirely powered by the shower circuit?)

Otherwise it's likely to be a simple failure in something, somewhere.
Fix it, or have it fixed. Normal diagnostic rules apply.