Need help on PBS Dependant Extension

[nctk]

Hello Sir/Madam,

I am on British Passport now, my wife is still on PBS Dependant which expires on 14-03-2015.

Initially, she applied 'Tier 1 General Dependant Visa' on 31-Jul-2012 from India and came to UK on 01-Sep-2012.
She got PBS Depedant on 14-Mar-2013, sametime I had been granted ILR.

My question is - Can I apply for PBS Dependant extension for my wife or do I need to apply FLR(M)?

If I need to swictch to FLR(M), can I still apply ILR for her in Aug'2017?

Thanks
Kumar