$startsWithArgs = "";
        $changeToOpts   = "";

        Attachment::chunk(100, function ($attachments) use ($startsWithArgs, $changeToOpts) {
            foreach($attachments AS $attachment) {
                if (starts_with($attachment->file_uri, $startsWithArgs)) {
                    $newURI = $changeToOpts. explode($startsWithArgs, $attachment->file_uri)[1];
                    $attachment->update([
                        'file_uri' => $newURI
                    ]);
                }
            }
        });