Lovastatin/Cholesterol 2% for DSAP (Porokeratosis)

I'm curious if anyone has feedback on their experience or results with 90+ days of Lovastatin/Cholesterol 2% treatment for DSAP. The instructions for post 90 days is 2-3 times a week for maintenance. But that seems dramatically different from twice daily for 90 days. I am at week 13 and do have noticeable improvement using this but I am not 100% clear. I'd like to hear from anyone who is using this treatment. My dermatologist suggested that there aren't any studies on twice daily treatment past 90 days. I don't want to apply twice daily as the cream is expensive, however i would like to maintain what progress I have made. Thank you in advance for sharing your experience.