@Moomin37 The 3-month prescribing only came in once the shortages were in place. That was about 18 months ago.
Some women have always been on a 3-month repeat as Drs like to review their progress. (This is the case with loads of drugs, even ones like thyroxine what someone can be taking for life.)
I used to be prescribed 6 months of HRT at once (if I wanted it - usually I took less as I often had a couple of months in hand) and my consultant said he was happy to prescribe 6 months, then he'd want to do a review. The legal guidance on most drugs incl HRT is a review at least once a year.