This has been asked for a few times, so it has now been added.

The booking calendar screen now includes tenants who are long term tenants.  They will be displayed in a grey colour, and will not be selectable for edit or payment taking etc like the short term tenants, but they will be there.

This mainly benefits people who have properties that they sometimes rent to long term tenants and sometimes short term tenants e.g. during the holiday season.  Because now you can see when the property is actually available for short term tenants.