Which towns/cities or regions of the UK are served by one region for BBC and another for ITV?
The Border TV region was never matched by the BBC. Even now it isn't - The English bit gets it's own version of ITV North East but has the BBC don't. The Scottish bit gets BBC Scotland and ITV Border. IIRC The Isle of Man gets the same on both
I was going to mention the Border region as there was never a BBC region that corresponds, even approximately. Northern Cumbria has been served by BBC North East for the most part, except for a period when I think was served by BBC North West. Southern Cumbria (South Lakes) may have changed hands between Border and Granada at some point, or perhaps I’m getting mixed up.
The IoM was always Border’s until quite recently when it went to Granada - and I think the BBC service was historically NE&C but has changed to North West. ISTR during the analogue days the transmitter on the island was fed by Caldbeck/Sandale but switched onto Winter Hill for the news opts only (as the feed from Cumbria was more reliable).
Was Berwick always served by BBC NE&C, despite receiving ITV Border prior to DSO? It would make little sense for those in Berwick to get BBC Scotland.
Berwick BBC 1/2 has always been fed from the Chatton transmitter. Chatton (which serves most of central and northern Northmberland) only came into service in 1974. The Berwick relay came on air in 1977, and as you say carried Chatton (BBC NE) from the outset.
Up until then viewers in the area had to get what they could long distance, I think Berwick was actually best served from Durris (Aberdeen !). Radio from there and the Scottish east coast romps into the town
Selkirk Border UHF came on line in March 1972 (BBC 1/2 Scotland followed in May 73) and fed Berwick
for ITV from 77 ) until it was switched to Chatton (Tyne Tees) in Dec 2006.
It was partly 'politics' and partly engineering, as with DTT
it complicates the SI/EPG tables if different
muxes are fed from different regional parents. Same reason the IoM became unified as Winter Hill dependant,
though that was a little more 'political', didn't Ofcom ask the islanders what they preferred ?
The south lakes relays are an exception. They were Winter Hill for BBC and ITV until Jan 1982, when they were transferred to Border, (but remained with Winter Hill for the Beeb). That continues post DSO, with special SI/EPG arrangements