XML : XSLT replacing one elements with multiple elements

I would like to replace an element in XML with multiple elements as below:

From (if release text() is A):

  <release>A</release>    

To (then replace with Aa, Ab, Ac):

  <release>Aa</release>  <release>Ab</release>  <release>Ad</release>    

For B would be: Bd, Be etc. My attempt works with one -> one replacement, but how to do multiple? Thanks a lot,