http://espn.go.com/nfl/insider/story/_/id/14712217/re-grading-2015-offseason-all-32-teams
Buffalo Bills
Offseason grade: B+
Re-signing key players such as Jerry Hughes and Kyle Williams secured high marks for the Bills last offseason even amid some concerns over the price paid for LeSean McCoy and the team's coaching change. What we missed, completely, was the impact Tyrod Taylor would have at quarterback. The Bills had Taylor buried on the depth chart when we handed out grades, so there was little outward indication the team had big plans for him. Buffalo scored significant offseason victories by adding Taylor, guard Richie Incognito and second-round cornerback Ronald Darby.
Re-grade: A-