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Back to headcodes, you could see some oddities between the penultimate stop and a terminus, or connection location, or a terminus. This would be because the driver/motorman might want to change ends or get away quickly and wanted to get out of his cab fast.
For terminii, often it would be the double red, for the Chipstead Valley line, often the train would arrive at Purley showing either two white or blank blinds to hook-up with the Caterham train. I am sure that at other locations there were oddities.
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