Guys,
If you issue emirates tickets by cash, make sure that u read the fare rules and conditions.Revenue tickets have two categories FLEX and SAVER. Flex fare doesnt mean that it is free to change date.Only difference between Flex and Saver ticket is, if you are a skywards member you can "earn more miles" on flex tickets and thats the only advantage.There is no other difference between Flex and Saver tickets.
If you issue tickets using skywards points, two categories are there.Flex(need more miles) and Saver(need lesser miles). Flex tickets are 1 year valid and date change is free, Saver tickets are 3 months valid and 25 usd per changes.