If you are very vulnerable shielding you can get your double up and save it for another time when you can get to the store by contacting customer service's. You have to prove this apparently.
The stores are supposed to only be selling essential items but our local large one, all aisles are open.
I will be going probably Friday to spend mine. I intend looking round first and seeing what I want, then get on the app and just change up what I need. Last year I changed them all up and then ended up buying stuff I wasn't altogether happy with, just to spend the vouchers. As you probably know, if you don't use them, you lose them.