Why the stocking type changed to "M" from "P" in item master table - F4101

Background:

Version : JDE world A73

Engineering department user reported some items ,the stocking type will changed to "M" automatically ,even they revised to "P" ,then it will be changed back to "M" .

I checked in table F4101 and found the last update by program P30601 ,I am not familiar with this program ,could you help to check the reason ? Thanks.

remark: not all items ,I suppose some parameters are not set up correctly and couldn't find the root cause .

Regards and Thanks.

Crag