Question about Dr Brown bottles

[lollylou1]

Annabelle is currently 7 weeks old and has been on size 2 teats as she has been on thicker easy digest milk, ive now put her back on aptimil 1, so ive but her back down to size 1 teats

When should she move to size 2 teats?

Lou
xxx

 

[Spartacus]

I think I remember buying the number 2 teats and it said from 3 months + but to be honest we tried it at about 8/9 weeks and it didn't work for Oliver but could be different as we give him expressed breast milk at night