RTAS had a great run, but that run is coming to an end. While there are still many Pro Tools 9 users, that number is dwindling rapidly. Mixers have moved on to PT10, PT11 and even PT12. RTAS has taken time to support, and Exponential Audio would rather spend that time on new development and support for more current formats. This means that RTAS support and development will be ending by the time the curtain falls on 2015.
How does this affect RTAS users?
RTAS versions of the plugins will remain available in the download area. Those versions will be frozen at the last stable build of 2015. If you're not ready to move away from Pro Tools 9, you'll still be able to download and use these versions. But Pro Tools support will move exclusively to the AAX versions. There will be no bug fixes or additional features for RTAS. It might be time to consider upgrading your Pro Tools rigs. Remember that your license is good for all formats.
Why bring this up now?
It seems only fair to announce this change well in advance. If you're still running an older version of Pro Tools, you'll need some time to plan for system upgrades. If you're considering a purchase from Exponential Audio, this could affect your decision. That's why this change is being announced over half a year in advance.
I don't use Pro Tools. How does this affect me?