OT(ish) sites down or worse

[Grizzly]

Hi All

OK it's 1st of a new month a lot of sites seem to be failing with

"The certificate is not trusted because the issuer certificate is unknown."

all for sites that worked faultlessly yesterday, most of the certificates will 
not expire untill late December

AskUbuntu (along with many others) has crashed on three of my browsers (so 
far), still testing others

did a Cert archive go down somewhere?