Not an official answer, but looking at Willam's list of patches, possibly1 they will provide output hotfixes for serious security issues and to support newer browsers for a year or two. But unlikely to provide any more application patches.
(Assuming this is what you mean by "supported")
1 No guarantee, just based on past form
Another point to make is what support are you referring to?
If you mean support as in issuing patches, then the previous post addresses that.
If you mean support as in if you phone Adobe for tech support, then I believe they will support 11 until the version after 2015 is released. However, there are always these forums for as many versions as people can remember using.
The usual main issue with older versions is browser support now that they get updated so frequently. For that you can continue using your version for as long as it works in the browsers you support.
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