National Trust for Scotland in England

[Bert2e]

I live in England but want to change to a National Trust for Scotland membership. Does anyone know how you park in car parks with machines that scan a barcode on your NT card with a NTS membership?

found this
How do National Trust for Scotland members park at National Trust properties with parking charges?

In all instances where parking barriers are enforced, these will be manned and you can show your membership card. While you won’t be able to scan your card in the NT ticket machines, you’ll still be able to park for free as long as you have your valid car parking sticker displayed on your vehicle. We’re currently working with the National Trust on a more permanent solution and we’ll update all our members once we have this finalised.

here:
singletrackworld.com/forum/topic/using-national-trust-of-scotland-membership-in-england-free-parking/
although it's a year old and no source is given.