To Sanjiv & Other blogers of this issue...
This extract from yahoo Answers can clear all doubts on season tickets... I hope.
Rules for Season ticket
1. (i) Rules, rates and other particulars regarding issue of season tickets can be obtained by application to the Railway concerned. Season tickets are issued for suburban as well as non-suburban sections. Fares for Second Class MST...
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is equivalent to the fares for 15 single journeys by second class (Ordinary) uniformly for all distances. Fares for First class MST continues to be four times the Second Class MST fares. Season tickets to children are issued at half of the adult season ticket fare. Quarterly Season tickets are charged at 2.7 times of the normal adult/child MST fare. Season tickets are issued for First and Second classes only and these tickets are valid in the class for which they are issued. Only one season ticket is issued to a passenger to travel between the stations serving his place of residence and place of work/studies. If the passenger is found with more than one season ticket to flout the distance limits, the additional season ticket will be treated as invalid. First class season ticket holders are not allowed to travel in AC coaches. On specific sections where there is sufficient demand of first class season tickets and it is not possible to attach first class chair cars, zonal railways may attach AC Chair car coaches, if available, for exclusive use of first class season ticket holders. On those sections, where there is no first class service, first class season tickets are not issued at all.
(ii) Distance : Season tickets are issued upto 150 Kms. only. Season tickets for more than 150 kms are issued only on those sections where they were being issued prior to 1951 (except on those sections where they have been withdrawn due to lack of demand).
(iv) Validity : Season tickets are not valid for travel in reserved coaches and trains. They are valid for travel by Passenger trains. In the case of Mail/ Express/Superfast trains, they are valid for travel by only those Mail/Express/Superfast trains where it has specifically been permitted by Railway Administration. However, they are valid for travel subject to the distance restriction otherwise applicable in individual train. The first class season ticket holders are, however, allowed to travel in first class coaches during day time only, subject to the distance restrictions applicable on the concerned train.
(vi) Superfast Surcharge Ticket: Wherever permitted by Railway Administration, the passenger can travel in unreserved coaches of Superfast trains also. In such a case, he is required to purchase the Superfast Surcharge ticket for each journey in advance. For the convenience of passengers who want to travel regularly by Superfast trains, the Railways also issue the Monthly/Quarterly Superfast Surcharge tickets on demand. The superfast surcharge will, however, not be levied on season ticket holders travelling by those superfast trains, which have total journey less than 325 kms from train originating to destination station.
Cheers...