Thanks for that. And yes, you're right, the miles expire at the end of a quarter while the status expires end of February of the following year.
Another thing I do remember, from a previous experience on a reward booking I made when still a SEN (companion award at the time) for the two of us, was that when we travelled, the BPs still showed me as a SEN, even though this was some time after me being a mere FTL and, therefore, we got use of superior lounges!