Hmmmmmm, it is always difficult to give advice on weaning baby birds. You definitely do not want to force wean them but on the other hand I have heard of people who are still offering supplemental feeding months or years after a bird should be weaned.
Those extra spoon feedings may just be for fun and a bonding experience for the birds and owners and suspect may be more for the owners rather than the birds.
If you have a scale it is best to weigh your young parrot each day before he eats anything. If he is truly ready to wean he will be maintaining weight without spoon feeding.
Is he flying, fledging and weaning typically come close together with fledging coming first. If he has not fledged then he is surely not ready to wean.
Does he beg when he sees you or when he is alone? A bird who is begging when alone in a cage is very likely hungry and in need of a feeding. Young handfed birds associate being fed with people, so if he only begs when he sees you it may be filling more of a social need then a physical need, in which case you could offer treats by hand or see if he responds to other social interactions. Again, this should be along with weighing your bird so as not to deprive him of needed food.
An occasional head bob and begging noises which are quickly abandoned may also not call for spoon feeding, but persistent begging or begging along with frantic actions is definitely the sign of a hungry bird.
If you unsure of what your birds begging means then go ahead and feed him.
When your bird indicates the time is right then you can drop the middle feeding and feed first thing in the morning and last thing at night.
Always feed him if he is hungry, every bird is different and a weaned parrot can revert when moved to a new home so a little supplemental feeding doesn't hurt