As it is possible, to install more than one complication of your app in different slots of the current clock face, it would be better to call 'reloadTimelineForComplication:' for all active complications.
for (CLKComplication* complication in CLKComplicationServer.sharedInstance.activeComplications)
{
//NSLog(@"Reloading Timeline for Complication: %@", complication);
[CLKComplicationServer.sharedInstance reloadTimelineForComplication:complication];
}
From the docs: CLKComplicationServer.activeComplications: This property contains an array of CLKComplication objects, each of which represents a version of your complication currently displayed on the clock face. This array typically has no entries or only one entry, but it may have multiple entries if your complication is installed in more than one slot on the clock face.