Isn’t this info now out of date as JourneyCheck now listing Didcot-Paddington shuttles now running to/from Swindon so only one change now required?
I think it depends whether the Bristol - Swindon service connects at Swindon with the hourly service from Newport (in which case a further change is needed) or with the electric service (in which case no further change is needed). Moving feast - lets's keep an eye on it (and please update / add comment into the original as appropriate).