Thanks for the chapter!
Seems Mrs. Mason has inherited the royal family's ability to act rude, insensitive and intrusive without getting called on it. After all, it's basic good manners and common courtesy to send word at least several days in advance to give the hosts time to adjust their schedules and make arrangements. For starters, a properly arranged room and food for her isn't the only thing that needs to be done, but also for her servants and guards accompanying her along with their horses and her carriage. Although how can she be a princess from a neighboring country not from around here and still related to the royal family? Or is it a close family member like a brother, sister, mother, father, aunt, uncle, or cousin is married to the king or someone from the royal family and that's the relation? Considering she brought up the Duke I'd guess that she's bears a similar temperament along with disgust for the politics and shenanigans from all the two faced officials and nobles. Then there's the motherly view (even if not blood related,) that her perfect little boy is too good for anybody and the wife nowhere near good enough to kiss his feet.