I'm very much in your situation - 59, 1124 CAC a year ago, walk 3-4 miles daily and do tension band exercises every other day. Just consulted with a cardiologist and reduced my rosuvastatin from 20 mg/day to 10 due to muscle pain and concerns about cognitive issues. I only agreed to that because my LDL profile is pattern A, I have great lipids due to 3 years eating LCHF (TG/HDL ratio is 1.2 and has been that for years, LDL particle size is also great) and I'm highly insulin-sensitive - fasting insulin level is 3 and my Quest insulin sensitivity score is 5 - anything below 33 being insulin-sensitive. Your question about where the Ca is located is intriguing and I hope you are right it could be outside the arteries.

Edit - ultimately I'd like to drop the statin to 5 mg/d or even eliminate it - statins are far less effective than the medical orthodoxy leads one to believe (they like to use relative risk reduction, not absolute risk reduction, in their studies - rant over 🙂 ).