iOS's auto connect introduces a number of unpleasant corner cases that can be difficult to deal with.
One annoying error path is if you delete the bond data on the peripheral but not on the iOS device. When iOS auto-reconnects, it will not do any IOs that would cause the switch to encrypted mode and detect that the bond is broken/lost. So it just sits there doing nothing. For something like ANCS it is the peripheral that initiates the service (by writing to a CCCD). In my current implementation, I do not do anything ANCS related until the encrypted session is established.
Is there a way for a peripheral to force a central to switch to encrypted mode? Or is there a clean way to terminate the connection if the central does not switch to encrypted mode. Just doing the obvious and disconnecting after a timeout if not encrypted just causes iOS to reconnect again, which eventually puts the peripheral on auto-connect black list.
