The rules change according to trend/support & reversals.
Any rule for trend is opposite to that of reversal and vice versa.
When calls gets added into the system at crucial support and puts unwind it means put writers are covering their profits and calls are getting added impending reversal.
There are only 4 rules and they dont change. BTW. Calls dont get added at support. They get added at resistance. Puts get added at support.
Long Build Up
The underlying asset will be consider as creating Long Build Up when both Price & Open Interest Goes up. When price goes up with Open Interest, there is expectation from derivative segment for the stock to go up further.
Long Unwinding
The underlying asset will be consider as Unwinding the Long Position when both Price & Open Interest Goes down. When price goes down with Open Interest, there is expectation from derivative segment for the stock to go down further.
Short Build Up
The underlying asset will be consider as Building Short Position when Price goes down & Open Interest Goes up.
Short Covering
The underlying asset will be consider as Covering the Short Position when Price goes up & Open Interest Goes down.