Moving on from breastfeeding

Sorry this isn’t directly breastfeeding related.

I am wanting to try and stop the lunchtime breastfeed now that my boy is 1 year old and give him cows milk. This is so I don’t have to express anymore whilst I am at work. I will still be breastfeeding him at other times of the day for the time being.

Anyway, I have been trying to give him the cows milk in a sippy free flow cup as recommended by health visitor. However he refuses it. He will drink the milk fine out of a bottle.

My question is, are there any other cups I could try instead? Straw cup? Or is this not recommended for milk? And if that doesn’t work, how bad would it be for me to continue giving him the milk in the bottle even though he’s now passed 12 months? I am in the UK by the way. Not sure if guidance is different elsewhere?

I feel like this is a minefield knowing the best thing to do.