I have been speaking to Dahua support in Australia and they advise the following.
"To save the msg on iPhone the app has to be awake by unlock screen or click on notifications. This limitation is caused by iOS design. We could not do much about it."
So yeah, looks like it cannot be fixed.
The account is the solution for notification on iPhone, however it seems to break two way audio on the TiOC's.
Also what I hate is needing multiple accounts because once you sign into a device with the account it signs the other out. Not convenient when users have multiple devices.
Regardless of the accounts or local adding I have reports of clients getting random notifications with no actual events associated with them, yay. (iPhone Only)
Also the latest Android app playback is broken unless you use an account. Have rolled myself back to 1.95 for the time being. Latest reviews on the app store confirm this is an issue. I have not had any reports from clients on this issue yet, that doesn't mean its not happening though.
Not great going into Christmas holidays!