Hi Drax
The only thing you can be certain of at this moment is that her ESA is being paid. Once they have made a decision you will hear from them.
Hopefully, they have accepted your doctor's advice, regarding an assessment but it is not a given.
Be aware that if you do receive a continuation letter they are worded so badly that it's not even obvious, that's what it is.
if it is the worst-case scenario and the decision is to stop her ESA it will be from the date on the decision letter.
BIS
Nothing on this board constitutes legal advice - always consult a professional about specific problems