I think increasing would be a good move, it is a known strategy for problem bleeding. Although bleeding can be expected in the first 3-6 months of a new conti regime this seems excessive. You may you find you're better on a sequi regime, at least you'll know when the bleed will come.
Are you certain you're meno rather than peri? I think I would ask for a scan to see if the lining has thickened or if there is another explanation for it. If it's build up perhaps they will be more helpful at getting a mirena for you - often it's the first thing they suggest. Is there a sexual health clinic you could try? At 47 it could easily be for contraception.
