The SMS revolution in India brought with it a lot of mobile phone tariff plans. The favorite among students and grownups alike is the discount top up. It allows pre-paid customers to send their SMSes at rates as low as Rs.0 to about 20p. But the mobile phone carriers saw the loophole. Lakhs of rupees of revenue was now being lost due to the fact that habitual SMS senders were now enjoying lower rates especially during the holiday season.
To counter this drop in revenue, mobile phone operators devised a plan. They earmarked the days of the year when the SMS traffic is maximum, namely
Republic Day , Independence Day , Diwali , Holi , New Year
And they changed their policies, so that SMSes sent on these days would be charged as per the normal non-subsidized tariffs. Till now its OK, but the fact is that many customers were not told about this and in this way the great Indian Mobile phone robbery was pulled off.