Hello, I am a director of a Family Day Care Service. We are currently implementing the updated standard for porta cots (of how they are only to be used short term) and replacing them all with permanent cots in all of our Educator homes. My question is, when is a baby considered to be old enough to move out of the cot and sleep on a mattress on the floor with other children in care?

Red Nose recommends that the safest place for baby to sleep is in a cot that meets Mandatory Australian Standards.
There is no specific age when they move from a cot to a bed.

Red Nose (& other safety organizations) recommends sleeping baby in a cot that meets the Australian Standards, until at least 18 months of age.
https://rednose.org.au/article/where-to-sleep-a-child-who-has-moved-from-a-cot

For safety reasons, when a young child is observed attempting to climb out of a cot and looking like they might succeed, it is time to move them out of the cot.
This usually occurs when your toddler is between 2 and 3 ½ years of age but could be as early as 18 months
https://rednose.org.au/article/making-your-home-safe-before-moving-a-child-from-a-cot-to-a-bed

There are of course other issues of safety to be considered when a child moves from a cot.

One in particular is:

If a child is wearing a baby sleeping bag whilst sleeping outside of a cot be careful!
A child wearing a baby sleeping bag and not confined to a cot is at a higher risk of falling and being injured.
The child must be actively supervised and the sleeping bag removed as soon as the child wakes.