10mg tablets are available internationally. I don't know about the UK.
Because of the very long fluoxetine half-life this won't be a problem (I don't advise it for other ADs). However, it can lead to mistakes and I suggest you only do it for a couple of weeks before going up to 40mg. You're probably not going to get much of a boost from 30mg anyway. Plus, with antidepressants it is probably better to be a little over than under medicated.Probably a stupid question but if I took one tablet and then two the next and then one the next and then two and so on would that be the equivalent of 30mg's because of the length of time these take to work or would it cause problems by leading to an imbalance?