Highly unusual pour moi, but HomeKit and the Home app are actually working with my Rachio3/16 as of today. I have firmware 632, a Linksys EA9500 with a Linksys Range Extender RE9000 to get to my garage 50’ from my home. I also have an eeroPro network but that doesn’t reach the garage so my Rachio3, the MyQ garage door controller, and my car are all connected to the Linksys network. I have it working on the 2.4GHz band; the 5GHz band is a bit weak in the garage although the car does pick it up well.
Usually Home and HomeKit are the last technology thingies that actually work for me, and many of my IoT devices still don’t connect properly to HK. I’m very pleasantly pleased that my Rachio3/16 now can control each and all of the 13 zones I have. Good job!
iPhone7 on iOS 13.5