TTE needs to remain in the AC train at all times. However queue system would be difficult to follow since there would not be any separate PF for AC locals.
All the pax would come to PF to board a local. Normal local would follow after departure of AC local, hence how to remove the non AC local commuters from PF at the time of AC local departure. This will be a challenge for the authorities since the PFs are too crowded during peak hours.
Regarding the demand of AC local-yes, there...
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will be a huge demand in future once the frequency is established during peak hours. but if only 1 rake is available, it means all the AC passengers need to ensure that they are on time daily to catch that local. It is not like a metro that if you miss one, you will get another in next 3-5 minutes. AC Locall with one rake means if you miss one, you will get another only after 2 hrs, which would lead to reduced interest in this train initially.
However, to begin with all the existing first class ticket/pass holders may be allowed to board the AC local. This would give relief to the first class passengers a lot since currently they are paying 8-10 times extra money for no extra facility on locals.
This will ensure guaranteed demand for AC local even with a single rake.