Thanks for your replies. I had not realised there were various camping areas, as when I googled Andermatt Camping, the only hit I got was Gotthard Camping. The tent I use is a Khyam Nimbus and the mat an Outwell Dreamcatcher 7cms airmat. I had planned to make this trip in July, before the pandemic changed all that.
The plan was to camp a few days at Andermatt in order to tick some local passes off my bucket list, before carrying on down to the Rimini area, mainly to visit the Marco Simoncelli memorial/museum. Then head home via the Stelvio and revisit Grossglockner.
I found the average September temps for the first fifteen days of the month to be 53/37F high/low. However, after seeing the pics of snow, although this may have been an abnormal occurrence, I’ll have to have a rethink. Being in my 70’s and usually Billy no mates, the possibility of being caught in snow might be biting off more than I can chew. I’ll certainly get down to Italy providing the Covid situation doesn’t worsen, but it might be better to consider Andermatt for next July.
On the subject of bag liners versus over bag covers, which type would offer the greater increase in low temp comfort, and which manufacturer would be favoured. Thanks again for all your suggestions and comments.