Hello Kiran,

First of all, let me explain you concept

1) Any model has only one write method (any model does not contain same name of method)

2) write method always get called when record modified (not at the time of record creation because at the time of record creation, create method call)

So in your case when kanban stage change or when record modified by other way write method always call.

When  you change the stage through the drag, there is a many2one field (stage_is something) will change.

so if you want to differenciate then do one thing:

check in write method that stage_id is in vals or not. If stage_id is in vals then it means that stage is changed. otherwise record updated normally.

I hope it will helpful for you.

Let me know anything that can i help you.

thanks and regards

Haresh Kansara