I would agree on modernizing the whole unit. If they think lead times are bad just for the door board wait till you need a clc or selector board and if you need replacment software your really going to be in trouble. Being proactive will save a lot of headaches.

Plus with the serial communcation it wouldnt be possible to use a different operator anyway. Its my understanding DMCs could only use a HD series operators, if Dover ever had a job with non standard operators like freight doors or a MOD that used a different door operator they would have to go with a IBM relay or LMH controller.