Where are Weatherfield's Golden Girls?

Has anyone else noticed the strange disappearance of two of our Corrie faves? Whatever happened to Liz McDonald and Deirdre Barlow? Liz managed to be part of the Owen/Jim storyline without actually appearing in a single scene. Possibly the last sighting of Deirdre was during Ken's meeting with his long lost family. There are probably good, valid and maybe even personal reasons why Anne Kirkbride and Beverley Callard (who recently got married) are away. Here's hoping for a return soon!