(12 Dec 2021, 5:21 pm)citaro5284 wrote You could have a bus say leave Consett and by the time they get to the Redheugh Bridge there is an accident on it and it needs to be diverted say across the Tyne Bridge and miss out Central Station, but when the bus left Consett, nothing was wrong.

Well that’s different, that’s an unplanned thing. You wouldn’t need anything on the destination screen for that as during its diversion over the Tyne Bridge you aren’t going to have people trying to flag it down, (or you shouldn’t as that bus number wouldn’t be listed on their bus stop).
Passengers already onboard will be able to see there was an incident or the driver ideally would explain they’re going to have to divert.

Surely the whole point of a diversion symbol on the destination screen (from the beginning of the route) is to notify people boarding that there is a planned diversion and they should check if they need to alight at a different stop to usual, should the bus be rerouted away from their normal stop.