"Paul Terry" wrote

Massive disruption across the SWT network this afternoon as a result,
including cancellations, diversions and late running of up to an hour. SWT
Dorking service cancelled, and Exeter/Salisbury services terminating at
Basingstoke. Even the Windsor line and Hounslow loop line were affected.

Presumably some Main Line trains diverted via Chertsey and Staines, getting
in the way of Windsor and Hounslow Loop.

Peter