PBS Dependent Extension + ILR Main

[MubaZaara]

Hi
I have got my ILR recently and my wife and daughter short of 4 days to eligible for ILR (5 year route)

Visa application 18 July 2014 and stamped on 19 Sep 2014
The current visa expires on 16 Aug 2019 with 28 days rules short of 4 days .

So I planning to extent the PBS dependent visa for 3 years ( 4 days delay cost 5000)..

Here is my question on application.
I know we need to select last permission grant visa (Tier 2 general) not ILR( even we don't have option on application)
But BRP do I need to provide ILR BRP or Tier 2 BRP which is not valid anymore ?