The work is still ongoing, we have had the following update from our DC Operator, we will provide further updates when available:
All works are now complete, however during a firmware upgrade to the various components within the B-side UPS, we have run into an issue which means we still have this UPS in bypass mode at present.
We are working to a resolution on this as we speak, however at present, B-side power - while restored in terms of delivery to client racks - is running without UPS protection at this time.
So while full power has been restored to all racks (following the works to the B-side today), full restoration of UPS protection on the B-side is still pending at present.