Option replace?

If the watermark has changed, you must:
1.Recovery original images.
2.Install a new sign.
3. If some of them should not have a watermark, then you need to manually delete the new sign where it should not be. If the watermark has changed, you must: send it for recovery. to install a new sign. If there are many images is it problem.
I would like to have the option to replace the old sign with a new one only where it exists.
Thanks