When to switch teats?

[SJT]

Hi ladies
I was wondering when I should switch my baby to size 2 teats. He is 3 months, I know they age them at this but he is still doing fine on size 1. We use tt anti colic plus bottles xxx

 

[OmarsMum]

when ur LO starts taking longer while feeding, sleep while feeding, goes off his bottles, or seems unsettled while feeding. xx