When should DS start taking his milk from something other than his bottle?

[Holymoly321]

DS will be 1 next month and currently has his three daily milk feeds in his avent bottle. He has water during the day either from his Tommee Tippee basic beaker (the ones with the fold up spout and handles - no valve) or from a doidy cup if we're at home. When should he be drinking all his milk from a cup? Should I start trying to give him his milk in the TT beaker?

I'd try and switch over now. It's supposed to be better for their teeth.

They say around a year because of tooth decay, if he really loves his bottle before bed try giving him his ay ones in a cup and his night one on a bottle.