OpenIMU300ZA: Settling time

Regards to OpenIMU300ZA, we noticed that usually it takes 15-20 minutes in the start to settle down and then it gives the proper heading information. Is this normal behavior and how can we reduce / eliminate this settling time for proper heading information.

pls refer to topic_11:
https://forum.aceinna.com/topic/93/top-topics-of-common-operations-with-openimu-products/2

after mag-align, hope will met your request.

we are doing mag alignment and getting soft iron>0.9, still the reading takes 15-20 minutes to settle down to a final value.
what could be the reason and how to solve it.

could you provide some log file?