What category does my (expired) residency permit fall, when it comes to UK visa applications?

I am making an application for UK visit visa, and on the online application, there are 2 particular questions, one asks (keep in mind I am paraphrasing here) "Have you been granted any visas to the UK in the past 10 years" and you have to fill out the type of visa, issue and expiry date, and issuing authority. The second one asks "Have you been granted leave to remain in the UK in the past 10 years" for which you also have to input a type, issue and expiry date but this also requires a "home office reference number".

When I was in the UK for my degree (2011-2014) they initially only gave me 2 years of Tier 4 Student Visa, some time during the 2nd year, I asked my University about this, and they told me it was an error made by the home office, apparently they missed a small detail in the 'extra notes' section of my CAS. My uni said they would handle it, and ask for it to be amended. They took my passport, and around 3 weeks later gave it back to me and it had another sticker/visa stamp on it that was valid for the duration of the 3rd year. However this sticker looked very different from my original visa sticker, for example it had the text 'RESIDENCE PERMIT' printed on it (although it did still list the type as Tier 4 Student), and in the 'Remarks' section, it said this was a "Limited leave to remain in the UK under ... ..."

My question is, should this 2nd visa go under "Visas granted" or "Leave to remain"? If it is the former, then what would be the issuing authority? It doesn't say on the visa, it just has a location (Sheffield). If it is the latter, what would the "Home office reference number" be? There are many numbers on the visa, one starting with "UK" then a bunch of numbers, and the other starting with "G" (not my initial) and a collection of letters and numbers after it.

Thanks.