If it was VIR in metal conduit I would be far less worried as fire risk fairly well contained.That's impossible with VIR as its in conduit, and if it isn't in conduit then that a whole other problem as it is single insulated cable.
It is the open stuff that would worry me, even if the CU change adds RCD protection that might catch faults that are enough to start a fire but not so high as to trip a MCB fast.