dovecot - Jun 2017 - doveadm sync SSL error when upgrading from 2.2.27 -> 2.2.29

I'm starting to see the following error from doveadm when upgrading from
2.2.27 to 2.2.29.
> doveadm(ip.add.re.ss): Error: doveadm client disconnected before handshake:
SSL_accept() failed: error:1417A0C1:SSL
routines:tls_post_process_client_hello:no shared cipher
I'm using a cert/key with the following curve.
  ASN1 OID: prime256v1
  NIST CURVE: P-256

Downgrading to 2.2.27 resolves the issue.  Does anyone know about this off the
top of their head?  If not I'll try to git-bisect 2.2.27->2.2.28 for any
offending commits later on this week.

-- 
Matt Pallissard