Adobe stop selling the old version immediately the new version is available. Support seems to last 5 years from release. 10.0 is ancient by the standards of software, released in 2010. 11.0 (XI) was released in 2012, so we can expect it to be supported until 2017 (next year); Adobe do not sell it. The current version is DC.
DC is available in a subscription model, which includes updates. I'd recommend this for those concerned with support.