You have 3 months left in your current support contract.
In case you RENEW your Rebex Support Contract, the new support contract period will add 1 year to your existing expiration date. So your new Support Contract for Rebex Secure Mail will expire on 2015-09-01. It's 12+3 months from today.
In case you UPGRADE your license to higher Rebex pack or to more developers, the new Rebex Support Contract is created starting from the day of upgrading. I.e. your new Support Contract for Rebex Total Pack will expire on 2015-06-01. It's 12 months from today.