Ray – running unified firmware on an up to date Raspbian image. both latest and recompiling meant the git pull (force) and rebuild. SO behind on so many personal things that I feel bad I havent had a chance to look at your code and sniff the response the sprinkler is getting when it does the update. I will span the port off of my switch that services the AP on that end of the house and look at the packets during a weather update and if interested can post those to a public wireshark area for you to look at. relies on my honey do list, kids baseball and work to calm down a bit.
Really thinking this has to be an artifact from multiple upgrades and an option remaining in place that causes this to go south and the best path for resolution isnt to make you folks tail after this but see if a reimaged card and install WITHOUT importing the options from the app/file does the trick.
On a different note – love the OpenGarage – can I suggest a twist of it? Mounted on wall in front of the vehicle and using it to key vehicle arrival AND light a remote red/yellow/green LED for parking purposes. Again – if I had more time I can see everything you need is right there but time time time. Also – was thinking of whether I could use the door path sensor (photoelectric eye) that exists on the garage to trigger a pin on the unit to know when thats been hit i.e. not only did the door open BUT something passed through or when I leave the garage door open (long way from the garage to the front door and friends like to surprise us by coming in from the garage) triggering a notification that somebody/thing just passed the beam.