I have been on Camzyos for over a year. In fact, I started this string in the beginning when I was trying to get my first prescription. Here are my thoughts on your post.
CVS Specialty Rx has never dropped the ball.
They send email reminders each month and ship express 1 to 3 days to home or local CVS ..... your choice.
You must have fewer than 10 pills on hand in order for them to ship.
Yes you call Rx every month and talk briefly to an intake person and then transferred to their Specialty Pharmacist who asks the same safety questions each time. It's their professional responsibility and for your well being. All seem to be very competent and very friendly.
Refills are 30 days max. Dr may write a script to cover 90 days (3 refills) but only 30 at a time.
BMS nurse navigator has become less of a factor over my experience. Some delays in receiving order could have to do with payment by third parties who are involved in your account (copayment, a grant, valid credit card, etc.). Ask the pharmacy intake person each time if payment is clear as they should be able to give you an answer from their screen.
Hopefully this has been helpful and that Camzyos works well for you. I praise and thank God every day for the incredible brains that invented it, and the entire team (although not perfect) He has placed in my life to help me get it! All is good! Persevere and try to be positive and at Peace.