More car parking spaces have been much needed at the station which is located on the GWR▸ line from London Paddington to Taunton and the Southern Western Railway route from London Waterloo to Yeovil Junction.
hmmm....you sure about that?
Castle Cary sees several South Western Railway services each weekday.
Indeed, and one of them (at 13:45 Mondays to Fridays) is a through train that starts at Yeovil Junction and goes all the way to Waterloo
.
Next Saturday and Sunday, there is a two hourly Waterloo to Exeter via Castle Cary and Yeovil service; I suspect the direct Salisbury to Yeovil line is closed for engineering. It doesn't actually call at Castle Cary, so I don't suppose the extra parking spaces will be much use in that case!