Ability to set Gutenberg compatibility?

We are on an older version of Field Manager and are reviewing Gutenberg compatibility for our theme.

We are trying to mark several metaboxes as incompatible with Gutenberg so it will default back to the classic editor if those fields are present.

The setting for this is added to the add_meta_box() call according to this documentation:
https://wordpress.org/gutenberg/handbook/extensibility/meta-box/
`array( '__block_editor_compatible_meta_box' => false )`

The add_meta_box() method in FieldManager doesn't seem to allow for an extra attribute such as this, however.

Am I missing the proper way to approach this?
Is this added in a version later than 1.0.0?
Will a Gutenberg compatible version of the plugin be released in the near future ahead of the merge with WordPress core in 5.0?

Thank you for your time and effort in maintaining this plugin.