If a child is wetting the bed at night and wearing diapers for the bed wetting then the child should remain sleeping in the diaper until they are dry through the night.
There are no age limits for diapers and once you have your child used to wearing diapers at night then they should continue to wear the diapers until they keep the diaper dry at night.
That could mean that if the child is wetting the bed at 8 years old and 10 years old then they should continue wearing diapers.
You can buy youth sized disposable diapers online once the child outgrows the baby diapers and regular diapers work much better than pull ups do.
Then when they get older and outgrow the youth diapers you can buy adult disposable diapers online.
Only have the child or teen stop wearing diapers at night when they wake up in the morning with a dry diaper.
It's much better for the child or teen to wear a diaper to bed and pee in the diaper than it would be to wake up in a wet bed.
I used to wet the bed as a kid and I wished I had diapers because I woke up every morning in a soaking wet bed and soaking wet clothes and that was miserable.
The diaper would've been much better.