query regarding potential backdated ESA

So due to the news that has came out about the DWP underpaying claimants it looks I have been identified as one of these people and got a letter last week from the DWP.

This letter required me to fill in a ESA3 form, and I have as a result of that information had to send in bank statements for the entire 4 years identified but I was told over the phone if I Cannot do for the full 4 years just to send what I can, since I feel they only need to see from the point I got my DLA lump sum, I sent from the few weeks before that to the end of the period so from 2014 to 2016, but the period covered is from 2012 to 2016.

I have looked here at some information.

www.gov.uk/disability-premiu...what-youll-get
and
www.gov.uk/disability-premiu...rt/eligibility

From 2012 to 2016 I got no disability premiums at all and I was in the SG on contributionicon based ESA.
I had no other income and savings below £6000

It looks like they are preparing to qualify me for backdated IR topups, which would add enhanced disability premium, for most of the 4 years, I think there would be a few weeks where I wouldnt qualify because I got a backdated DLA award which took me over £6000 for a few weeks.

However there is also a normal disability premium, the qualifying criteria is stated as getting some form of DLA and not been on IR ESA.

This is where my questions are focused.

So

1 - If I was backdated DLA for a period of 2 years, am I counted as been on DLA for those 2 years? or just from the date I was given the backdated lumpsum?
2 - If I am counted as been on CB ESA but with IR ESA topups, how does that work for the normal disability premium, when it states not been on IR ESA I am assuming it means you must be on CB esa, which I was, but its confusing as it might mean if you on CB ESA with a IR topup you still dont qualify.

I want to know as it may mean I am owed more money than originally seemed, obviously I appreciate any advice on this matter.