How to deactivate routing to/from a custom table

If you decide you no longer wish to use a custom database table and instead load/save data to/from core meta tables only, you may remove a custom database from the map system by deleting the associated JSON file then rebuilding the table map system. 

First, deactivate the table definition management on the field group's admin screen. 

Do this by setting the Manage Table Definition to false and saving the field group. Note that this toggle does not control routing of data, it only controls whether the schema blueprints will be modified when the field group is saved.

Next, locate and delete the JSON file used to inform the table creation/update process. 

If using ACF JSON, the files will be within the acf-json/database-tables directory. If not, they'll be in the wp-content/uploads/acf-custom-database-tables directory. If you are unsure, you can find the path in the create/update tables file list as per the screenshot below. You may find the target file by looking for the table name within.

Finally, run the create/update tables process to rebuild the table map system

Head to Custom Fields > Database Tables > Manage Tables (tab) and run the create/update table process. This will rebuild the map used to route data in/out of custom database tables as well as apply and changes to the database that may be pending from changes to field groups.