Victor Font Staff replied 4 hours ago

There is no way to effect a change like this without custom code. Formidable stores checkbox values either as a single text value or a PHP serialized array depending on whether you have multi-select enabled or not. It's not hard to change a single value, but if you are using multi-select, you have to extract the serialized array, unserialize it, make your edit, serialize the array again, and replace the current values in the database.

It may help if you take a look at how Formidable stores its data using the metadata schema. You can find instructional videos here: https://formidable-masterminds.com