acnebride, I started 'relactating' when ds was 6w, and within 3 weeks I had gone from 6 x 7-8oz bottles per day, to 2.5 x 7oz per day. I met someone at a bf support group who, like you, was starting at about 10w and I know that she managed eventually to drop all the bottlefeeding, but it takes a bit of determination and luck! Personally, I was delighted by my own results .
What worked for me was to put ds to the breast at every single feed, and between if he asked (by now you probably know when he's hungry as opposed to bored or windy etc), and not to give him a bottle until it was clear that he wasn't satisfied. So I dropped the first bottle -the 'breakfast' feed - because I was always fullest at that feed and gave him just bm. He had been feeding at almost exactly 4h intervals, but without the bottle his intervals shortened. I avoided feeding him at less than 2h intervals, but nonetheless fed much more frequently, probably 2-3hourly until my boobs got used to making more milk and then the interval settled at 3-3.5hourly.
I found that I needed to drink a lot, and rest as much as possible. Basically I just sat on the sofa with everything I needed within arms reach until about noon. Sometimes I didn't even get dressed until my sofa session was over! Remember to eat well, but not excessively.
I just had a look at ds's red book, and his weight-gain slowed very slightly between 6-9w, the sort of slowing-down that wouldn't even have been noticed if I had been weighing him monthly instead of weekly.
By now you know your little man very well, and you will know if he's doing well or not. Weight really is not an issue! My dd, who was exclusively bf (and still is bf at 15m - I feel quite triumphant ) gained very slowly, even levelling off at times, but was absolutely fine in all other respects: pooing, weeing, contented, developing well.
Sorry, long blather, but this is a situation close to my heart! Good luck, and do keep us posted - Mumsnet really is super for support and advice.