In that case 1990 Keswick would have BG and SG with both in use.The Crystal Brook to Dry Creek standardisation was opened December 82 - extended to Mile End in early 1983
When was the line from Adelaide to Port Pirie converted to SG?
Steamranger's BG Southern Encounter would use APT Keswick before their enforced move to Mount Barker.Then there is the story of a Bluebird consist with at least one vehicle of the wrong gauge. it was recognised by the guard when he took the consist list to the driver, he noted that the same car was on a BG or SG train he crewed the day before. Truth? Good story, Yes!
I seem to remember a photo or two of the Mount Gambier Bluebirds (BG) and the Broken Hill Bluebirds (SG) both at Platform 1 ready for departure in opposite directions.