@john0 Thanks again for this pointer. I switched the app to “Not optimized”, and so far it seems to be making the difference. My wife’s phone was suffering notification delays of 10 minutes yesterday, whereas my phone was much more immediate. I don’t want to say instantaneous, but certainly within an acceptable range.
Since then we’ve switched off optimization on the app on her phone, and the response times have have improved considerably.
Of course, it could be coincidence, so I’m still monitoring, and I’m hoping that the phones’ battery life doesn’t suffer too much.
@Mengdi or another mod - could you please add “Video Doorbell” tag to this thread so it shows up in the right place?