I saw this as well, however on both of my trips in May they were saying Euston.In my trip in April the displays were saying Edinburgh in Dundee as well. Don't think that was the case before.
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Yes, but Inverness is the starting point of the service to Euston, the Aberdeen and Fort Bill portions join onto it.Perhaps, Aberdeen are able to show the train as Euston because it is the beginning of the journey and therefore doesn't require tracking on the service.