Every time I come back from a trip abroad I receive a notification telling me how much I spent abroad, but once I delete the android notification that information is lost forever (or at least I wasn’t able to find it anywhere).
It would be nice to have a section listing all the messages the app sent as a notification, and in case of the travel report having something similar to the monthly spending report.
The notification shows, but actual report&item in the feed are hidden, since Android doesn’t have this functionality yet. I guess it’s not doable to easily switch off notification, since they are kinda valid for both ios and android. I’ve been confused too. 
Once this feature is available (post Current Accounts rollout or with it - for Android users), it should be available historically - just like monthly spending report is placed. I could see historical reports when I opened Monzo app on ios, just needed to scroll back/search.