The NPLTime® commercial service provides a time signal to the end user over optical fibre that is independent of GPS and certified by the National Physical Laboratory (NPL) as being traceable to UTC(NPL) at the end user. A trial of the service was conducted at the UBS facility in the LD4 datacentre in Slough, where the signal was consumed and assessed within the UBS infrastructure to validate the source, internal distribution architecture and systems, and timestamping solutions. The trial was carried out over a leap second implementation and included a period of fibre outage, demonstrating the resiliency of the service and engineered redundancy solutions. The time offset of the signal from UTC (Coordinated Universal Time) was measured by transportable disciplined caesium clocks from NPL. The solution was proven to be capable of achieving approximately 100 nanosecond synchronisation to UTC(NPL).