The BBC has the story now:
https://www.bbc.co.uk/news/uk-england-67241554
Travellers face disruption next month when the railway line between Guildford and Gatwick Airport is closed for seven days.
The North Downs line, which links Reading and Guildford with Redhill and Gatwick, will be renewed from 11 and 17 November.
Work, including upgrading 1,089ft (332m) of 1970s track, will take place during the week.
Network Rail said the £1m investment would benefit customers for years.
During the closure, bus replacements will run along the affected line. Trains will continue between London, Redhill, Reigate and Gatwick, but the line between Guildford and Reigate will be closed.
I am surprised that, for a whole week closure, the works are only costing £1m - minor by today's standards. Only 332m of track are said to be going to be renewed. However, as there is no mention of what other works may be included it's hard to grasp the scale of the works.
Also, assuming that Southern are still to run to Reigate (as the BBC item says), there is no mention on NRE of the availability of those - the message implies no trains at Reigate, just from Redhill.