Thanks Frank, I was already trying to send a loadbang, but the first [instance] has the right id (1), then the following [instance] has id = 3, the next 6 and so on. Besides also other instances of [instance] with different arguments are affected the same way while sending a loadbang to the parent patch.
You can test this in the example patch I sent yesterday.
Probably I'm missing something, but I'm struggling to make it work without good results.
Maybe Luke is reading us?