Hi Mr Quite Happy,
From your posts did you do 2x AMS-LCY-AMS ie 4 return flights or just 2?
I assume as you state your target for Silver is 400 tp's is that your Executive CLub account is in Europe ( as for UK residents it is 600 points)
On your online account page, even if you exceed the point requalification it still says you need 4 qualifying flights.
It does take a few days once you earn the points for your account to be updated to Silver.
As far as I know the BA cityflyer flights do count as BA metal.
I would give your BAEC centre a call.
Regards
TBS