Grace, if you are taking enough estrogen, then you WILL bleed.
Fact.
You will either bleed randomly and erratically with breakthrough bleeding (because you are trying to take your progesterone continuously) OR you will schedule the bleed by stopping the progesterone to cause it to happen, so you know it is happening due to the progesterone being withdrawn and not for any other more concerning reason.
So if you bleed today and consider it to be day 1 and then your next bleed doesn't happen for 40 days or 50 days - despite you stopping your progesterone for it to happen - then it means you are not taking enough estrogen. Take a look at the work of Dr Felice Gersh on YouTube for more information, especially her video on estrogen dosing. Or join the FB group called 'Bio-Identical Hormone Therapy' which has flowers as its icon. It's one of the largest FB groups for HRT and is US based along the lines of optimal HRT and not micro-doses at suboptimal levels.
Estrogen is proliferative. That means that IT WILL cause endometrial build up, if you take enough of it.
And you want to take that much of it, because you need those aspects of it - it is about cell turnover, anti-aging and mitochondrial health amongst so much else. If you are not taking enough to cause endometrial build up (to the point that nothing comes out when you stop progesterone) then you are also not taking enough for all those other health benefits, at optimal levels.
Eastside - yes, see Dr Felice Gersh on YouTube and Instagram (she has longer videos on YouTube). And as above, if you don't bleed (when you stop the P, given enough days for the hormone shift to happen) then there hasn't been enough build up which means the estrogen has been too low. (This happened to me, by the way.)
Conti regimes are dead in the water as far as HRT goes. At no point, ever, in our entire life cycle, do we continuously have progesterone. Never. It is not bio-identical to take progesterone continuously. The only way it can happen (without bleeding) is when the estrogen dose is so low, there is no build up happening and the progesterone is heavy-handed and suppressing that. In which case, you are not getting the other benefits of the estrogen elsewhere in the body either. Continuous progesterone down-regulates the estrogen receptors as well.
You have to understand that HRT (and the guidelines and the info on the packets etc) is still based on the mass hysteria originating from the WHI. Even now that doctors are begrudgingly prescribing HRT again (in many cases), they are doing so with great nervousness around estrogen, being worried about too much of it, and as if it is somehow dangerous. It results in micro doses which may well reduce the baseline risk for various health conditions, over someone who doesn't take ANY HRT, but it's not 'optimal' because they are scared of it. So the approach is these tiny micro doses of estrogen and heavy handed huge doses of progesterone (partly because they can't even test levels of progesterone accurately in the UK since most women take it orally). There is far more estrogen in the combined pill they happily prescribe everywhere like smarties, (albeit synthetic estrogen) than there is in standard HRT doses, yet they don't even realise the hypocrisy of this....