So based on their github and some searching with google, historically they didn't have much of an end-of-life policy, because there were
no bugfix releases for v1.x.x after v2 came out, and no bugfix releases for v2.x.x after v3 came out:
v3.0.0 - 2013-08-19
v3.0.0 RC1 - 2013-07-27
v2.3.2 - 2013-07-27
v2.3.1 - 2013-03-01
v2.0.0 - 2012-01-31
v1.4.0 - 2011-11-03
v1.3.0 - 2011-09-16
With major version 4 still being in alpha, there are concurrent releases of 3 going on still, but based on their previous releases, I don't expect a v3 bugfix release after 4.0.0.