We have an installation of hybris including the B2B module running version 5.2.0. I can't find (anything that makes sense to me) on the wiki or hybis webpages that categorically states when 5.2.0 is EOL and the date this will occur. I have some reports that this is to occur Q4 2016, which if true is unfortunate as we only finalised the implementation of an upgrade to 5.2.0 in Q3 2015.