When do you start to change formulas from a stage to another stage ? Example stage 1 to 2 , 2 to 3 ? Do you really wait till exact months or age to change to another stage ?

I do wait till exact month to change. But it could be a gradual change. Below is a link that explains on how to transition from one stage of Friso milk to another or introduce Friso if you are using it for the first time. https://external-sin6-2.xx.fbcdn.net/safe_image.php?d=AQCPV0XQATT6WZ6_&url=https%3A%2F%2Fmedia.giphy.com%2Fmedia%2F3o6ZtqcttXaTJi7dYY%2Fgiphy.gif&ext=gif&_nc_hash=AQBorxbzNfdFDrvv

Promo terbesar expert care sudah dimulai, diskon hingga Rp.100.000 sedang berlangsung di shopee, ada juga voucher diskon 100% alias gratis bagi bunda yang beruntung. Buruan cek di https://shope.ee/9UfEMMqqTg (id-27311)

if the formula happens to finish 2 weeks before LO turns the months ready for it, i will move onto the next stage. gradual change as how some mention above

If the stage one formula is finishing 2 weeks before the suppose stage 2 age, i will change to stage 2 I won't wait till exactly the age to switch over

You can change it slightly earlier. no need to follow everything exactly. that's just a guide

I don't wait till the exact months, i usually make my purchases before hand.

not really cos bb will be turning to that age in a few days.