Solar + Batteries + Span + Gas Backup Generator

Wrestling with a fairly complex setup at home. About 9 years ago I had a 9kwh system with a single inverter to my existing natural gas backup generator backed config. We lose power about once every other year for up to a week and the generator has been a savior.

That said, I still want to keep moving to be more energy independent, so we’re planning to add another 6kwh of panels and a pair of batteries, and ideally a span.io panel.

Of course plenty of challenges. Span is not aware of automatic transfer switches, and currently there are two sub panels off the mains (ATS/generator panel, and optional devices panel).

I think the only way i can do all this is (in terms of fallback order):

city power -> batteries -> generator (via ATS), and then the span

Unfortunately, the span ends up not knowing anything about the power outage because it has no way to talk to the generator.

What do your complicated setups look like? Anyone got ideas for how to get more value out of the span with this sort of config?