I don't think you can even be prescribed Qlaira ( with bio-identical oestrogen) beyond 50 - but if any of them are low risk well that one is, so it is possible a doc may well be prepared to do so in the circumstances. I think it is the stronger synthetic oestrogens that are not recommended in "older" women. Unfortunately with the POP you don't replace oestrogen and some of them also depress oestrogen levels which is probably not the best idea in early 50's if you are well into peri-menopause.
Darlingbabs - HRT in the usual doses does not shut down the cycle which is why some women don't get on with it in very early peri-menopause. The Mirena though will give a constant level of progestogen thus flattening out the fluctuations ( although ovulation still takes place in many women) and the constant oestrogen dose also prevents the low dips which normally occur during the last part of the cycle.
Hurdity x