11109 worked RE3821, the 14:04 from St.Gallen to Chur, south from Altstätten SG on 8 May 2013.
The loco is one of only two to still carry the orange and grey Swiss Express livery introduced for crack Genève - Zürich - St. Gallen expresses in 1975 and originally applied to the eight Re4/4iis dedicated to the service. Remarkably two locos still carry the colours over 30 years after the Swiss Express designation was dropped and both appeared on the St.Gallen - Chur service in the two days I was in the area.