I have an elderly family member, who got taken in by this same type of notice.
It had been less than a year, since she had any activity, so her miles were obviously not expiring, but she was coerced into subscribing to magazines that she would not have been interested in, under normal circumstances. She apparently got "taken" twice by this practice, which greatly reduced her account balance.
YX - please put some pressure on this "partner" to revise their practice. I am sure there were many people, who mistakenly were lead to believe that their mileage status was "use it or lose it."