We're a bit off topic here discussing the IETs north of Edinburgh, but one piece of gossip I've heard locally on the Highland Main Line is that the Chieftain may be making additional calls once the HSTs are away, presumably because each stop will be a lot slicker without a long line of mk3 slammers to deal with. Dunkeld has certainly been mentioned in this context, which makes sense since its annual entries and exits aren't that far behind those of Kingussie. I haven't heard anything on Aberdeen services.
Ironic of course that (some) all stations services are being provided by slam door HSTs at the moment, but there you go.