The one that upset me was Elleste Duet, and I persevered with it for over a year. I got a pharmacist friend on to it (GP wasn't interested) and he reckoned it could be the inactive ingredients (colourings, coatings of tablets etc) and suggested Climagest which has been perfect. It has exactly the same active ingredients as Elleste - oestradiol and norethisterone.
I've since been doing a bit of homework and the only difference I can see between the two is the colourings - Elleste has a yellow colouring and Climagest blue. So I'm now going through all the possible alternatives to see what colourings they have!
As for it being discontinued, this was what I was told at the pharmacy last month - they were unable to dispense my prescription in full and could not order any more, telling me I'd need to go back to GP for an alternative.