For example, if I receive a WhatsApp message, it seems to disregard DND entirely and just ‘pings’ as normal. Looking at the notification settings for WhatsApp, the option to "Allow interruptions (Receive notifications from this app even when Do Not Disturb is enabled" is NOT turned on.
In any case, it’s not just that app. My calendar app (aCalendar) is among others that exhibit the same behaviour, which makes me think it’s more of a problem at OS level. Again, this app is NOT set to ‘Allow interruptions’, so that isn’t the answer. Perhaps not surprisingly, the developer for aCalendar confirmed that they believe it’s an OS issue rather than one that they can help with:
"aCalendar does NOT use the alarm channel, but the notifications channel. We use standard Android mechanisms for notifications so your DND settings should be correctly applied by Android.To configure this, please go to aCalendar settings – notifications – (events|birthdays|tasks) – notification channel.There you should see an option to configure if DND is honored or not, however this screen is outside of our control (in your case it is governed by Huawei)."
I have contacted Huawei who said they’re unable to replicate the problem, and because it’s an isolated issue, surprise surprise… I have to do a factory reset and then return the device if that doesn’t work. Those are both absolute last resort options as far as I’m concerned, so I thought I would post on here to see if anyone else has come across this issue (on the P20 or any other device). Or perhaps someone with better knowledge of Android could speculate as to how this problem could come about?
Any advice/info would be much appreciated – thanks.