iOS Mail App not doing Scheduled fetch and notifications for favourite mailboxes on IMAP mail accounts that do not support Push (Yahoo/ Gmail / IMAP accounts)- fetching in such favourite mailboxes only on manual opening.
Observed behaviour:
iOS Mail app is not performing the scheduled fetch for favourite mailboxes of IMAP accounts (like Gmail, Yahoo and third party IMAP accounts) which do not support Push. The behaviour does not change with any of the frequency of scheduled fetch - 15 minutes, 30 minutes, or hourly. Scheduled fetch does not occur with any of the frequencies on favourite mailboxes. Mails are not fetched on schedule from any of the favourite mailboxes even after a lapse of many hours/ multiple fetch cycles. Notification for any mail in favourite mailboxes is also not being generated with any of the possible options for selected scheduled fetch frequency.
The scheduled fetch works only for the Inbox of an IMAP type mail account (not supporting Push) and not for any of its favourite mailboxes of non-Push type.
Upon opening the Mail app, the respective favourite mailboxes of non-Push IMAP accounts shows unread count displayed against each. Only the unread count is shown but the actual mail is not fetched. The notifications did not happen for those mails in favourite mailboxes.
The notifications occurs for Favourite mailboxes only if its mail account supports Push, or it is manually opened.
This erratic behaviour occurs irrespective of whether the iPhone is connected to the charger or not, network connectivity is WiFi or cellular.
Expected behaviour:
The native iOS Mail app should perform scheduled fetch and notifications on favourite mailboxes for IMAP/ Gmail/ Yahoo mail accounts which do not support Push. The scheduled fetch should should work as per any of the selected frequency out of the available options (hourly/ Every 30 minutes/ Every 15 minutes). Every favourite mailboxes should get fetched in each fetch as per schedule and no such mailbox to be missed and left out from any scheduled fetch.
A notification should get generated for every new mail fetched in such favourite mailbox of IMAP account which does not support Push.