I wrote a letter through him, requesting that I be released from the Navy early, because of my opposition, and I was granted that release, and I have been working against the war ever since then." -----John Kerry, June 1971
Kerry's own website has his
DD214 (pdf format), which tells a different story: he wasn't separated from active duty until 17 Feb 1972.
Pinging FL_engineer because he is mentioned in this and in your post.
I'm not going to go back and look it up, but I saw that dd214
and the date you mention sounds correct.
Its not correct to refer to it as 'active duty' though is it?
Because he was in the RESERVES even when he 'won' his medals.
and I believe the date you mention is the date his
reserves committment was to end.