Tesco is one of the supermarkets I reached out to last week and my order with them is due today. The website is fairly accessible as is the app . I had to call them to be placed on the priority risk as a visually impaired person and although they are unable to take an order on the phone they are usually very good and reasonably priced. On their toolbar they have a button for priority slots which you have to click one once you have registered as a vulnerable customer
Tesco are now accepting Severely sighted impaired people as being in the vulnerable group for online shopping. To register call 0800 9177359. If you are Sight Impaired (Partially sighted)just to see if they will accept you to the list.
Tesco did respond to my MP and have said they are looking at opportunities to increase the number of slots available and to help support those most in need, including recruiting 8,000 new colleagues. They have also said that they can liaise with local stores to explore how they can help constitents to want to shop in store especially with social distancing guidelines in place.