I can't be exact, because it was almost a year ago now. But I remember feeling myself on a steady upward trajectory until my first three month prescription ran out, which was from a private doctor, and then getting my second prescription from my own practice, which was administered by my local pharmacy - over days into weeks I started to go back to feeling how I had prior to going onto the gel.
I said to my husband that I felt like it had stopped working. It was different packaging to what I'd got privately - that came in a cylindrical pump while the local chemist one was in the shape that all oestrogel comes in now. I came on here looking for answers ... read the thread saying they are exactly the same and let it convince me I was imagining my return of symptoms.
Then my husband suggested going back for another private prescription - did that, it arrived in the same shape packaging to the one I'd got locally and I thought 'well, it can't be the gel then - it must be me.'
However, I abandoned the chemist version just in case and went onto the privately bought gel ... within a week I was feeling great again and back on that upward trajectory. Brain fog gone, energy back up, sleeping well. I know my pharmacist very well and talked it through with her - she said 'I gave you a parallel import last time - next time I'll give you the UK one and see how you get on'. That's what we did. It worked just the same as the private clinic prescription gel.
After this experience I will always insist on non-parallel imports WHATEVER the medication I've been prescribed.