@WombatChocolate You might be a bit confused over a few things.
But many women start HRT far before this, and so suffer painful bleeds, PMT etc for a long period to 54, which for many will be long after their periods stop…but they don’t know they’ve stopped and don’t want to go continuous before it is ‘right’
Do you mean women having their own natural periods or on HRT?
Some women have no bleeding on sequential HRT (about 20%.)
Some women have a light withdrawal bleed.
Some women have a heavier withdrawal bleed.
It's assumed that by 54, 80% of women are post meno. That's why continuous is suggested if they want it. (There is no absolute rule.)
If someone is not actually post meno then, yes, they might get a natural period, that is not controlled by continuous HRT. But most won't.
Your idea of trying it for 2-3 months.
The guidance is that it takes up to 6 months for conti to work and for no bleeding to occur. This is because it can take that long for the 2 hormones to work together to keep the lining thin.
Breakthrough bleeds
In younger women using continuous too soon, breakthrough bleeding (often continuous spotting or very light bleeds) is a nuisance but nothing more.
In older women who have used conti for some time and then have bleeds (after the first 6 months) it creates a scenario where they might be sent for investigations. It's always assumed post meno bleeding is possibly cancer till proved otherwise. (RCOG guidance). Obviously, HRT complicates this as most women who have bleeding on conti are fine and it's a hormonal blip. Some women on contil still have a lot of their own estrogen = bleeding- so the guidance says increase the progestins first to see if this helps.
It's all explained here www.menopausematters.co.uk/postmeno.php
The other reason for continuing with sequential is it's been shown to have a lower risk of breast cancer than continuous. (by about 1.3% in some studies.)
If someone is on HRT long term, this might be a consideration.
Sorry for the essay!