Meanwhile United skipper AlbertWatson appears set to stay at Ballymena after talks with manager Roy Walker, having previously handed in a written transfer request.
Gary McCutcheon put United in front but Gary Hamilton (2) and Kyle Neill gave Glenavon a 3-1 lead before late strikes from AlbertWatson and McCutcheon.
David Cushley, Noel Anderson, Gary Muir and Nathan McConnell are also being released by the club but AlbertWatson and Aidan Watson are among the players mulling over new contract offers.