Limit Statuses available by current status?

I figured this out. I am not a coder but this does the job for me.

1) Limit available statuses based on current post status. This is a modified version available on the “extend” page of the plugin.

Basically, $permitted_statuses lists all possible statuses which you want to allow users to choose from at any given stage.

Then, I used $permitted_on_initial, $permitted_on_assigned, and $permitted_on_inprogress to limit available statuses based on these stages.

For instance, I am allowing draft to only show when the status is in progress.

—————–

function efx_limit_custom_statuses_by_role( $custom_statuses ) {
    $current_user = wp_get_current_user();
    // $post = get_post();

    switch( $current_user->roles[0] ) {
        // Only allow a contributor to access specific statuses from the dropdown
        case 'contributor':
            $permitted_statuses = array(
                    'initial-idea',
                    'assigned',
                    'in-progress',
                    'draft',
                );

            $permitted_on_initial = 'initial-idea';
            $permitted_on_assigned = 'assigned';
            $permitted_on_inprogress = array(
                    'in-progress',
                    'draft',
                );

            // Remove the custom status if it's not whitelisted
            foreach( $custom_statuses as $key => $custom_status ) {

                if (!in_array( $custom_status->slug, $permitted_statuses ) || $custom_status->slug =='initial-idea' && !in_array( $custom_status->slug, $permitted_on_initial ) || $custom_status->slug =='assigned' && !in_array( $custom_status->slug, $permitted_on_assigned ) || $custom_status->slug =='in-progress' && !in_array( $custom_status->slug, $permitted_on_inprogress ) )
                    unset( $custom_statuses[$key] );                               

            }
            break;
    }
    return $custom_statuses;
}
add_filter( 'ef_custom_status_list', 'efx_limit_custom_statuses_by_role' );

2) If you want the status to change as soon as the author loads the page editing page, which can be useful to track who started an initiate an e-mail or something, you can use something like this:
————

//------------ Start Swtich from Assigned to In Progress on post edit page load ------//
function educadme_assigned_to_inprogress( $post_id ) {
	if ( current_user_can('edit_post', $post_id) && !current_user_can( 'manage_options' ) ) {

				$post = get_post($post_id);
			    if (get_post_type()=='post' && $post->post_status =='assigned' && strstr($_SERVER['REQUEST_URI'], 'wp-admin/post-new.php') || strstr($_SERVER['REQUEST_URI'], 'wp-admin/post.php')) {
			    		$post->post_status = 'in-progress'; // use any post status
						wp_update_post($post);
					}
		}
}
add_action('add_meta_boxes', 'educadme_assigned_to_inprogress');

Again, no developer/coder here but I tested these and they work for me. If anyone have any suggestions or edits, please comment.

I hope some of you find it of use!

Glad you figured it out, and thanks for sharing here!

You are welcome! Thanks for this great plugin :).

Update: The code in #2 isn’t working as intended. I have posted a request for help on StackExchange. Hopefully someone will help me spot the issue and I would update it here.