According to to EL AL's Facebook page, the TSA has moved their security checks so that the KDL is post-security.

Good move in my mind (though LY had nothing to do with that), and benefit to LY pax.

Weird that they mention "First Class and Platinum Business Class passengers." Do they still use the term "Platinum" for the long haul C product? And no mention of TPLs/PLs/GLs? Hope that's not an LY downgrade

JFK has changed terminal 4. Apparently it was the only terminal that had the huge duty free area before security. They felt this was not smart security wise. Of course it means that there is no place to sit and visit with people who are connecting at JFK--or to hang out if you want to see someone off! ( they will lose revenue on the ridiculously expensive short term parking)

When I was there, enroute to Israel in December they were working on this. Anyone who knows the terminal knows the floor that you check in on has first the check-in counters and then the area where the lounges are. This area has lounges on the perimeter and a rather narrow walk that overlooks the duty free area below. The open area over duty free is/was huge. What they were doing is filling in that area so that there is no open air section and in essence making two complete floors--the check-in security floor and below it the duty free/departure floor. The new TSA security check is on the newly built floor. As I just returned to the US from Israel and won't be going back for a few months--I haven't seen it--but I hope that give a better idea.

Terminal 4 at JFK is being renovated, and security is on the same floor as check in, before going down to the duty free area.
Major works are also being carried out, to be able to handle all Delta flights which used to depart from terminal 3 (which is being closed)

I was in JFK KDL on Wed Mar-13 pm (waiting for LY7 at 7pm).
It is still on same level of checkin before security.
All gates are 1 floor down.

Which makes perfect sense considering LY's Facebook post said "as of today (March 14)"

The changes at Terminal 4 in JFK are part of a wider campaign by the PANYNJ to decrease the amount of non-flying passengers in the terminal. The same is happening in certain areas of Terminal B in Newark.

Yet in Terminal B, most lounges are still remaining outside security, even after the construction

The lounges restrict access on their own. It is the huge food/ duty free areas that are now closed off. ( as I indicated in my original response)

Never said they will be behind security, just that the changes are part of a wider effort by the PANYNJ to reduce the amount of non-traveling citizens in the airport at any one time.