I didn't switch the milk feeds to a sippy cup, instead I switched the milk feed (the 2 days milks) to a solids snack with a drink of water but your LO may not be ready for this yet. a lot can happen between 9 and 12 months and the process is perhaps not as gradual as you might think. What I mean is those changes (switching from milk to snack at the 11am ish and 3pm ish E) may seem nowhere in sight right now, but in a month or two they could happen over night with no fuss at all.
The advice to have them off bottles at 1yo is to protect teeth, they do still need a decent milk drink each day and if they don't take a decent amount from an alternate cup then keeping one bottle is fine. The main thing is not to be giving juice drinks in bottles and not to have them sucking from a bottle all day long, a quick 10 min milk feed in the morning or evening is not going to damage them. It's also important to switch around your routine so that teeth brushing comes after the BT feed if it isn't there already.
At 12 months mine was having 2 bottles, one at WU, one at BT. At 12 months I dropped the BT one over about 7-10 days a very gentle wean. At 13 months I switched the Wu one to a straw (not sippy). The WU one was harder as I needed that milk intake to stay constant but even so it only took a few weeks of trying and practise for the switch to happen without any drop in milk.
I used the tommie tippie sippy cups (no valve) which are in all the shops. For the straw I tried a bottle with a straw but found it hard to clean the straw so instead bought a big pack of straws (£ shop) and used a new one each day just popped into the top of a bottle/cup. I washed them all out and saved them for the craft box. We've had great fun doing crafts with them so I don't feel at all bad about using so many disposable straws!
