Hello, I switched my Android mobile from Nougat (Huawei P9 Plus) to Pie (Oneplus 6T) and found notification more unreliable:
1) impossibile to set vibration only notification

2) notification soud sometime is the system default notification sound, sometimen the one chosen in to the app

3) set values into the app are not catched, need app data reset (previous point still)

4) sometime notification is delayed a lot