Not to challenge your knowledge here, but what is your intended use for osta? You had said above that you primarily wanted it to retain muscle. IMO, the tapering you suggest doesn't exactly make sense - wouldn't it be more beneficial to find out the dosage that best feels like it keeps gains for you and then just keep that dosage consistent through PCT? As much as I love the "more is better" attitude most of us have, I've seen a lot of cases where people feel osta is incredibly effective at retaining muscle while at only 10mg daily. To be honest, your dosing looks more like it's trying to gain muscle from osta as opposed to keep what you've gained on-cycle. In PCT you want to make sure of two things: #1 that you do not interrupt the testicle kick-start and #2 That the compounds you take assist the testicle kick-start. That 30mg starting dose is, IMO, dangerously close to violating the first principle.
I know you're still researching it, but I wanted to lay in my 2 cents.