Theres no way to tell when and by how much your orgasms will change, but I can certainly share my personal experience.
Im about 3 months into HRT right now, and i have noticed some gradual changes in how my orgasms feel. It started with a gradually more "full body" experience and also i started to have better results using a vibrator instead of stroking. I first started noticing those changes around the 2 month mark, and they have gradually progressed since then. In the last week or so i have been able to have a second smaller (and dry) climax after the first, which is exciting.