The 80286 was released in early 1982. The IBM PC AT, which used it, was released in late 1984.
Two and a half years is a long time to design a new computer that is a fairly modest upgrade on existing technology, and a long time for new technology as commercially important as the 286 to go unused. I'm conjecturing that IBM felt they could take it easy because their PC already had technical superiority over the competition, but according to InfoWorld, in August 1982 there were already an estimated 60-70 companies with or working on PC clones; surely at least some of them must have felt the pressure.
Was there any computer, particularly but not limited to any PC clone, based on the 286 before the AT?