Apparently, things have resolved themselves quickly.
According to Alex Marvez of FOX Sports, Schiano was back in the office in Tampa this morning.
Rephrased @TBBuccaneers update: HC Greg Schiano back in the office after missing team flight home from Pats game to stay w/ill family member
— Alex Marvez (@alexmarvez) September 23, 2013
Source: Darin Gantt, Pro Football Talk