According to Daytime Confidential Stacy said it was a scheduling conflict after she landed a guest spot on FOX’s midseason replacement Ride-Along. She goes on to say she has no hard feelings. http://daytimeconfidential.com/
BUT
This is what she had to say on Facebook
For all you guys out there who were all set to watch me on DAYS I have some bad news. DAYS has dropped me. It all started when I booked a guest spot on a new show for FOX, RIDE-ALONG. The show will shoot in Chicago and I have to leave town for that. There was a conflict in scheduling so FOX pushed me to their second week. But when ONE day was still in conflict, instead of working things out, DAYS decided to drop me.