Mizter T wrote:

I guess there could be extra weekend engineering works on the NX Gate
to West Croydon stretch, but it certainly isn't going to shut.

AFAIK the only major engineering works will be just north of NXG where a new
bridge will be built over the mainline. This will presumably require more
than just weekends, but the existing ELL will hopefully still be running to
help people from points south to get into London (although capacity is an
issue). New junctions will be built just south (I think) of NXG, but I can't
see that taking longer than a weekend.