Anyone else having trouble with Chrome v55 and web filtering set to authenticate?

Haven't updated my firmware in a while, we're on 5.2.1.  We have social networking set to require authentication, so teachers can use it, but students can't.  Worked great until machines started updating to v55, now we get a "your connection is not private" error.  Chrome complains the cert uses SHA-1, and also gives net::ERR_CERT_COMMON_NAME_INVALID.   Is anyone else seeing it, and have you been able to resolve it?  Is this something an upgrade to the firmware will fix?