Last night's occultation of Io by Ganymede provided an interesting sight. The two moons could be seen converging for the occultation and then slowly diverging. After about 2 two and half hours the divergence ceased and the two moons started converging again for a second occultation. Unfortunately Jupiter had slipped below the horizon before this second occultation took place.
A transit of Ganymede's shadow was in progress during the first occultation.
So, and interesting sight as Jupiter sank low in the West
I use a Vixen NA140SS on a TRex mount with Argo Navis on a fixed pier. Works well for me.
I keep an eye out for all of the interesting Jupiter and other Solar System events, Minor Planet events, occultations etc. Weather and viewing conditions are problematic here on the coast South of Hobart. So, I miss some and catch some. Yes, I will be trying for the double transits you mention.