iLO itself is Embedded on the System Board.
iLO Advanced is a license applied to the iLO to unlock more features.
If they don’t fully factory reset the iLO before you buy, then any license would be still in effect.
If you have the serial numbers, you can dump an overly detailed report of the config as it left the HPE factory by putting it into partsurfer.hpe.com

T420 would be an HPE “Gen8” equivalent.

https://support.hpe.com/connect/s/product?language=en_US&cep=on&kmpmoid=4091408

Manuals, Downloads, etc

ATI ES1000 is part of iLO if I remember correctly.

Utah is my guess based on OPs profile

Cellular Phone Booth