I don't know if this is part of this thread or another one entirely.
My toilet and shower is full of my bedding when travelling, and folding table and chairs etc. I have no store at the back. So my loo is permanently unavailable.
Does anyone else use a public toilet app? I find that it covers my needs brilliantly, although a bout of D&V might put an end to that belief.
I use an app called FLUSH, which is very useful. It needs signal, but will guide you to your nearest public loo very well indeed.
It doesn't include pubs or many restaurants, but is good on public facilities. Saved my life a couple of times!