I've been a BE member for 12 years and have not gotten the audit email. Someone upthread mentioned they were told this is happening to "all" accounts, though not sure how accurate that is. I have just over $5000 spend over the past 12 months, and have another $3000-$4000 in the next 2 months. I also have 3 unique travelers, so I'm good to go into 2023 for redemptions. But since I only had around 700 points left, I redeemed a BXP1 to hopefully use in the coming year. I've also already redeemed 2 BXP3's for travel in a few months to Europe and those seats are confirmed (2 of us traveling).
In the event they do audit me, and are not satisfied that I meet the requirements, I'm going to assume they could just as easily take back those 2 upgrades (6200 points total) that are already confirmed but the flight hasn't happened yet. Fingers crossed....