Thanks for the info viewmont, I'm surprised by that if for no reason other than I had never seen the postcode showing the receipt as acceptable proof of shipping until several months ago, and when you go looking for what it acceptable proof of shipping on the site, the page stating that is very difficult to find (I can't get there via standard site searches or the user agreement). All of the ones I find by standard navigation say that the proof "must" show the recipient's delivery address. (https://www.paypal.com/helpcenter/main.jsp;jsessionid=7nlzQ1sBF1rpPLb9X5nn3q02GFmJTTcZspBnM0hcYRK5yhDtJblt!-692288800?t=solutionTab&ft=homeTab&ps=&target=_parent&solutionId=1206880&locale=en_AU&_dyncharset=UTF-8&countrycode=AU&cmd=_help&serverInstance=9016 

and

https://www.paypal-australia.com.au/business/business-resources/delivery-options )

In that case then, if PayPal have always deemed it as acceptable, then there have been a number of sellers that have attempted to use it as proof of shipping in the past but failed (anecdotally, based on threads that I have read here over the years, and I don't know what else those sellers did / didn't do throughout the dispute that may have contributed to the loss).