Your first solid clue that the Auburn Tigers are converting to a pro-style offense after losing spread magician Gus Malzahn to the Arkansas St. Red Wolves? The acquisition of prototype fullback Jay Prosch (250 pounds, two carries) from the Illinois Fighting Illini. The Tigers had no real use for such a player during Malzahn's reign, while Illinois' shift to Tim Beckman's attack means the Illini no longer do, either.
Your second clue: reports like this from John McClain, that Auburn is after Houston Texans quarterbacks coach Greg Knapp to fill the OC role.
@McClain_on_NFL Auburn is interested in Texans QB coach Greg Knapp as OC.
That would make two former Atlanta Falcons coordinators on Auburn's staff, by the way. Knapp, Atlanta's OC under Jim Mora from 2004 to 2006, would join Brian VanGorder on the Plains.
Knapp has also ran the offenses of the Seahawks (2009), Raiders (2007-2008), and 49ers (2001-2003), but has no college experience since working his way through the staff of his alma mater Sacramento State Hornets from 1986 through 1994. Pretty pro-style, I'd say.