I also had the same thing happen to me only on a 2 stop twin post synchronized telescopic. Make sure the cylinders are level to each other by removing jack bolts and buffing out the car and let the cylinders fully collapse away from the strike plates. Measure the distance between strike plates and top of cylinders and see if they are equal. The elevator will do a automatic resync usually once a week in the middle of the night and if the cylinders don't fully collapse onto the check valves you will have issues. Make sure Jack bolts are long enough to let the cylinders collapse away from strike plates and enough time in the parameter settings for the resync to work properly. You mentioned cleaning the up level screen. There is also another screened input on the oildraulic valve on the side behind a plate with 4 bolts. I believe it's part of the bypass. Carefully check it for any debris as well.