backup & clear receipt inbox

backup & clear receipt inbox

How can I backup the entire receipt inbox (other than downloading 20 or 50 at a time) and then clear it (of all reported expenses)? Thank you. 

Would really like to see a clean inbox if all expenses are reported (and even submitted, reimbursed). 
It is misleading (and demoralising) to always have a full, messy inbox containing a mix of fresh unprocessed receipts AND receipts already processed into expenses (in various stages of approval for reimbursement, archiving etc.) 
Processing the receipts that linger in the inbox again (which you never know until afterwards) will indeed create duplicate expenses that need to be (manually) merged/ cleaned up. 

Resuming subscription on a paid plan after having exceeded the auto-scan receipt limit (which is guesswork and a nasty surprise if caught late), does not pick up where it left off and so unscanned receipts already in the inbox need to be manually filled in (pushed along) or deleted and re-uploaded/ resent for auto-scanning. 

Is this "full inbox" thing a bug or a feature that I'm using wrong? Thanks. 
KR, 
Tibi