Apparently the Centrale shopping centre (which only opened in 2004) is
to be merged with the Whitgift Centre. I think this will probably create
the largest shopping centre in the UK, since the combined area of the
current centres is only just short of the Metro Centre in Newcastle.

http://www.bbc.co.uk/news/uk-england-london-41983441

This page suggests that East Croydon may gain a fourth pair of NR platforms.

https://en.wikipedia.org/wiki/Croydo...#Train_Station

The page also talks about lengthening tram platforms at West Croydon,
although I couldn't quite find enough info to make sense of that. I
would have imagined that all the tram platforms are the same length, and
there would be no point in lengthening one unless you lengthen them all.