Terminal B at EWR finally has a dedicated line at security for F/C. IME, they have always let me on when flying Premium Economy but I have no idea if that's official or they just see the word "Premium" and allow it.
Terminal B security is pretty bad. There is no Pre-Check (even if LY participated, it still wouldn't help) and the lines are crowded and move slowly. The only way to get through quickly is by being crew.
I have done it in a wheelchair and it took just as long - there is NO priority even for disabled pax.
The F/C line is indeed quicker, but still slow and painful.
You've been warned!