I have global entry and haven't gotten SSSS on my US boarding pass in who knows how long.

I am flying AA.

Last year I had a last minute business trip to to the UK. On my return I got SSSS and they told me I was flagged by US DHS. Today I went to check in for my next flight to London. Checked in just fine for the domestic leg but couldn't check in for the JFK to LHR leg. The check-in agent at BOS couldn't do it. I tried to have the Admiral's club agent do it and she was saying there was some message about needing UK immigration clearance. I finally went back to the check-in counter at JFK. The agent there checked me in without any issues in only a few minutes. But handed me a boarding pass with the dreaded SSSS on it. The rest of my family has precheck on their passes. We are on the same PNR.

So now I am trying to figure out who has me flagged and how I get unflagged.

And is there anything I can do before tomorrow morning to get the SSSS off my record?

Am I going to have this issue with the rest of my trip? I am flying from London to Dublin in 10 days and then back to Boston via London again.

Any advice would be appreciated.