Show if a Read Receipt is being requested or not

Every now and then I receive an email message which requests me to send a Read Receipt. While I don’t mind sending one, sometimes the timing is a bit unfortunate.

For instance, when I work late at night or quickly check my email during the holiday. Also, for one mailbox I’m only a delegate and I do not want to send out the Read Receipt for my manager.

Is there a method to easily see beforehand if an email holds a Read Receipt request or some way to send out the Read Receipt at a later time?