What is the effect of the drum switch in the "Advance" position on the rear of the train?

When the drum switch is in the "Advance" position, it indicates that the train is moving forward without triggering the Automatic Deadman Control Loop (ADCL) indicator in the head operating car. This means that while the train may be advancing, the systems that typically provide signals or operational confirmations related to ADCL will not be engaged or signaled in this position. The absence of the ADCL indication suggests that the safety protocols linked to the train’s operational status in relation to ADCL are not active, allowing the train to move through this setting without the standard checks that would normally follow. This highlights an operational method in train control where the "Advance" position allows for forward motion without a specific acknowledgment or activation of certain safety systems.