Can you pull down any of the wires to the existing ring?
- eg, run in capping or oval or loose in holes if behind skirting

In which case break the ring & just extend accordingly.
- so maintaining the ring structure
- so having all junctions directly accessible

Lifting floorboards sounds easy, but not when covered with a heavy
bed, carpet, fitted furniture or wood.

If redecorating it should be a non-issue to do it "properly". If you
do use a JB, note it on the CU re I&T.