I've checked instacart, amazon, and a couple local stores for delivery/pickup slots. there's no place on any of the web forms to indicate that you would be eligible for a priority slot, and I haven't found any news articles to suggest otherwise. my seventy-year-old parents are also unaware of any way to get priority slots, so I am assuming they don't exist. my impression is that the stores consider "elderly hour" to be an adequate solution.