I am very pleased to see these new buds appearing on some of the Yamadori Scots Pines, I removed the end buds in November last year and this forces the energy in the tree to push out onto old wood. I left one branch with the end buds on to see the reaction: New buds have appeared but they are weaker and less frequent along the branch. Last year I fed the tree with Tibolar and the tree was very strong enabling me to do this work. NO needles were removed prior to this technique.
New buds on old wood
So Many new buds
End bud removed in November the previous year
This is the branch where the end bud was retained
Wolf's Birding and Bonsai Blog 