In pre-COVID times, the routes from SOU to various destinations in northern England and Scotland were frequently very busy, with a large number of business users, together with a fair bit of ‘friends and families’ traffic.
To travel from the south coast to the north by rail involves journey times which are much, much longer than from London. For example, day return travel by rail from London to Manchester, Leeds and even Newcastle is a realistic proposition, and rail is a very viable alternative to flying. The situation from the south coast is very different, with the extended journey times making it virtually impossible.
However, I guess we are now living in very different times and I no longer travel up and down the country for business on a regular business, and it’s very difficult to see the previous level of regional domestic air travel ever returning.