Sterilising baby bottles

[Ab85]

Hi all,
About to ask a stupid question 🙈 But I’m a new mum and a bit confused about sterilising bottles! My electric steam steriliser says the contents is sterile for 24 hours if the lid is unopened. Does that mean that if I take out one bottle the rest need to be sterilised again? And you can’t just take them out as required over that 24 hour period? Sorry if I’m being silly! Overthinking everything at the moment 😂 Thank you!

Remove and assemble all the bottles and they're ok for 24 hours.

Take all the pieces out and put them together straight away as bottles, then they're good for 24 hours.