not in; went off to somewhere else temporarily; to go away for a short period; to go off for a moment, usually to go and do something else or to leave someone (or a scene / situation / circumstance) temporarily, with an intention to come back
a phrase to say that everything will be plain sailing after completing a certain task / passing through a certain stage; to do a slipshod job of something and trying to pass it off as done; to try and pass something off by deceptive means