Post study - Tier 2 - ILR Documents

I have been on Tier 2 visa for 5 years and now applying for an ILR.

Before my Tier 2 visa, I was on a post study visa for 2 years.

Now there is place in the form which states that the documents have to be provided for the following:

For the period before you were granted leave as a Tier 2 migrant, documents showing that
you met the relevant requirements of the immigration rules.

Could anyone explain what documents do they require for this?

That statement of that section 12P is not applicable to you as you are applying under5years on Tier 2 General route.

If you switched from any other category to Tier 2 general to complete 5yr period then you have to answer that (for instance 3yrs on Tier 1 and rest of 2yrs on Tier 2 General.