Immigration Rules Appendix 32D

Hi there

I've been seeing some contradicting information online regarding the english test requirement for FLR(M) applications for a visa extension for my wife.

It says in the rules that a previously accepted certificate which was used for a successful application, can be used for the FLR(M). Does anyone know if there are any exclusions to this?

My wife passed her Cambirdge English test at A2 Level in May 2013, we used this as part of the initial spouse via application which was accepted fine,

Any help would be appreciated on this. Thanks