Instead of a generic thank-you this fall, send each of your A referring offices a short, personal Year With You card before Thanksgiving.
Inside, have the doctor handwrite three things: the number of patients that office trusted you with this year, one specific moment when their team made a difference (a quick same-day referral, a thoughtful handoff), and a thank-you to their front desk by name.
It takes 10 minutes per office. It shows you pay attention. And it will be remembered long after the holiday cookies are gone.