For the first time trip, I'd go to Limpopo end of June first of July for a couple reasons.

It is very dry that time of year. Temps are nice and cool at night and pleasent during the day, maybe around 60 or so. It is mostly bush, so 20,000 acres seems like 100,000 acres where areas around Freestate and the such are a lot more open.

So again, what I like about Limpopo in June/July, no bugs, no rain, no heat