To disable Advanced Shipping feature, user should navigate to Setup > Company > Enable Features > Transactions > Shipping & Receiving > Advanced Shipping. Once user unmarks the Advanced Shipping check box, a notice is being thrown:
"The advanced shipping feature may not be turned off while there are outstanding bills on fulfilled orders."
To disable the feature, user needs to bill all the sales orders that were already fulfilled. Once orders were billed, a notice will be thrown again:
"Turning off this feature (Advanced Shipping) will also turn off the following dependent features. Multiple Shipping Routes, Shipping Label Integration, Pick, Pack and Ship and Multi-Location Inventory. Disable these features now?".
User will then have to decide if he still needs to disable Advanced Shipping feature.