Asda is the only supermarket from which I have been able to get click and collect orders since the crisis started.
I never used them previously, but they are offering a much better service compared to Tesco, Sainsbury and Ocado; good luck in finding any slots at all with those!
Some items are ‘out of stock’ which are available inside the store, but I guess they have to hold back some things that are in higher demand for availability to people in the stores.