I think it is long term and consistent, not drastic that works.
I am committed to 18 months to 2 years solid treatment, rotating azaleas and sections. Iver does nothing for me.
Then I will move to four times a year when no nips. Then twice a year forever.
You could try the Lufeneron with your regime. It targets hatching eggs and also encysted strongyloides. I think scattering would be covered by it. In your position I would think back to when you started treating heavily and consistently and aim at 2 years from then.