Hi Nicola - how many pumps of oestrogel are you on? You can take utrogestan continuously at any point, but often people who are not ready for it will bleed. However, if you were on a low enough dose of oestrogel (e.g. up to 2 pumps) you might not.
You could always try it and see how you get on. The heavy bleeding suggests you might struggle with bleeding while on continuous utrogestan but you won't know until you try. If you think about it, things like the Mirena and the pill can stop bleeding continuously so there is nothing inherently wrong in a no-bleed regime. It is more about whether or not it will work for you.
Alternatively, you could try a continuous regime of a progestin like Provera to see if you tolerate that. The Mirena seems to be best for stopping heavy bleeding but, like you, many of us just can't cope with the synthetic progestins (as good as they are).
Also, how do you take the utrogestan? More tends to be absorbed where it is needed (uterus) when taken vaginally. You could try it that way on a continuous regime and see if it stops the bleeding or, at least, reduces it to a more manageable level. If you are nervous about no break at all, it can be taken with a 3-day break only. But do some research and ask your GP to do the same - they are getting paid for it.
If your GP is a bit in the dark, it would be good to see a menopause specialist who can give the GP options that are known to be effective.
Also, might be good if they checked your blood levels for iron, B12, Vit D, etc, if not already done.