Attachments on different places than the aligners, does this make sense?

1. It's unlikely, as these things are pretty automated nowadays, but there may have been a production error by the aligner company.2. Attachments sometimes go on and come off at different stages of treatment. For example, you may have 6 attachments to start, but when the movement for some of those teeth has completed and they no longer need the extra help from the attachments, they may be removed. Also, some movement may only start later, once there's more space for a given tooth to start it's new trajectory.
Hope that helps!
*All advice/any statement made here should not be taken as definitive dental advice. The ideal way to obtain definitive information is with proper diagnostic procedures during an in-person consultation.