I wish you good luck, and will look forward to reading your update.
Hello, I took 10 months to withdraw. I have been well since I stopped 6 months ago, and have had no withdrawals at all. I am now medication free. You are on a very high dose. I was on 150mg daily for 5 years. Before that I did stop cold turkey after 4 years, but depression returned after a year. I am keeping my fingers crossed this time, that it does not return.
Good luck with your withdrawals. Let us know how you get on. Hope it works with no withdrawal symptoms. I do know that the very slow taper worked for me.