Infrastructure PE SA Technicals

For a SA role at an Infra fund (one that is purely infra, like BX or KKR, and not tied in with an energy fund), what kinds of technical knowledge is expected from an undergrad?  Have looked at prior threads but most seem to focus more on what IB analysts interviewing for an associate role should focus on -- wondering what a current undergrad interviewing for a SA / analyst role could best do to prep for the level of technicals generally asked to that level of candidate.  For context, I've been interning at a small LMM IB firm part-time since January 2020, will be at a BB IB for my soph summer and have some light RE exposure from a prior internship but nothing specifically infra on my resume (if that impacts what they could ask / expect me to know)

Thanks all!