Tommee Tippee - Closer to Nature - Microwave Steriliser

[DollyDynamite]

I don't understand - if the contents only remain sterile IF THE LID IS UNOPENED - then as soon as you open the lid to take out just one bottle surely all the other three bottles are then exposed to the air and no longer sterile? So what is the point in having space for 4 bottles at a time?

Department of Health guidelines state you must only make up formula when you are about to use it - and not prepare bottles in advance, so when would you need four bottles sterilised in one go?

Can you use