I was pleasantly surprised at the swiftness of this after the FLR(M) affair, and am posting time scales for anyone else undergoing this process.
FLR(M) expired end of January 2015
Posted SET(M) application 16th January 2015
My cheque was cashed on 23rd January 2015
A letter confirming that our papers had been received arrived 24th January 2015
A letter telling us to go for the biometrics procedure arrived 4th February 2015
My wife did her biometrics on 13th February 2015 (on the second attempt as the network was down for 48 hours!)
A letter arrived from the Home Office (dated 11th March) on the 12th March 2015 telling us the application had been approved.
A biometric residents permit arrived on the 13th March 2015!
I was quite impressed!