Gluten free level: expert.
They have gluten free bread and they have special gluten free big fry up breakfast all day. I ate their gluten free halloumi salad with baked vegetables. It was nice and warm. It was a huge portion as well. It's definitely worth a visit if you want some definitely gluten free food.
Disclosure: the place doesn't look fancy but the ladies at the counter were lovely. It is a good old fashioned breakfast and lunch coffee. Their prices are reasonable especially for Whitstable.