This isn’t exactly in my ‘wellbeing’ wheelhouse, but I will give you some suggestions.
Yes, pencil people in. As with anything, be open and honest about what is going on. Yes, you can book them in, but there may be changes depending on what the Government decides to do. People will understand that.
There are all sorts of conflicting studies around wearing masks. In regards to it being a virus, you need the proper surgical ones and the need to be worn correctly, which apparently not many of us are good at doing.
From what I’ve read, the fabric ones are not sufficient.
What you do have to do though is manage other people’s anxieties and expectations. Wearing a mask will help people think that you are taking their safety seriously. Explaining to them the measures that you are taking and they will have to take in order to have their appointment will put them at some ease.