I realize this may be far little too late, but knowing what we know now with S0 and some hubs, I really do think the issues you’re facing are from S0 and network flooding.
If you still have the bulbs (or anyone else who reads this that may have similar issues), I’d highly recommend upgrading to the beta firmware 2.31 where you can include the bulbs as, “non-secure” instead of the default of S0.