The notification issue seems to be mostly fixed on 14.0.6. I used to not get notifications for any app that did not run in the background beforehand. There are a few culprits such as Facebook messenger, but I heard that notification issues for that app also is present on other brand OS's, so it may be it's own problem, other than that it's great, and any app that does not work consistently, putting them on autostart, setting no restrictions on battery management and pinning then in recents does the job!
That's because in the beta build all apps are set to autostart, at least that's what I noticed on my end
