During the initial stage of the introduction of telephone Exchanges in India, many exchanges were opened with three telephone operators only. They were to attend 8 hours duty every day so that the exchange will be manned all 24 hours. They were neither given any holiday nor weekly off. If one of the telephone operators had to take leave (getting leave was almost impossible), the other two operators will have to share his work.
Now all officials in the telecom sector, including operators get paid Holidays, Sunday (or Weekly Off) and other permissible leave. It was only through sustained struggle for years that these achievements could be made.
The P and T Unions have a past full of sacrifices and struggles!