I have exactly the same issue which needs to be fixed.
I go on extended holidays and depend on my watering system doing its job and when needed be able to modify schedules. The timer has always worked as scheduled (which is great) but accessing it remotely fails continually due to no wireless. I have had to resort to getting friends go to my house and power the unit on\off to reset it.
The wi-fi simple fails and when this happens it then fails to to re-establish itself for what ever reason (it simply drops off and days later it magically comes back! or not..). The wi-fi in the house is stable (and strong signal at timer) as I have other remotely operated wireless devices in the house managed via Kasa which are always available
The BHYve timer info is:
MAC Address: 44:67:55:04:4e:b1
Firmware Version: 0039
Hardware Version: WT25G2-0001
Wi-Fi Version: 0