Hi Ostia
In my experience, it doesn't talk about the review date on those letters; it merely says that you are still eligible for PIP for the following year and reports on any change in the rates.
If you already have a 10-year award, you are likely to be sent the AR2 (light touch) review form when it comes to review time.
BIS
Nothing on this board constitutes legal advice - always consult a professional about specific problems