Moving car seat

[niamh29]

DD3 is nearly 3 yo and is currently 15.4kg, she is in a 5 point car seat, I know the min weight for moving to a high back booster is 15kg but is it safe to leave her in her seat for another while, she is very tall but seems ok in her current seat.

If her top of her ears are below the top of the seat, leave her where she is.
We have just taken 4y8m 17kg DS1 out of his 5 pt harness due to height.
She needs to come out before 18kg.