Blizzard is scheduling raid tests in Icecrown Citadel for October 21-22. 

The schedule is as follows: 

US PTRs 
October 21 at 7PM EDT / 4PM PDT - Festergut 
October 22 at 7PM EDT / 4PM PDT - Icecrown Gunship Battle 

EU PTRs 
October 21 at 19:30 CEST - Rotface 
October 22 at 19:30 CEST - Icecrown Gunship Battle 

Only normal difficulties will be tested, although 10 and 25 player raids will be available. 

The Icecrown Citadel raid test schedule will be very flexible, and can change at a moment's notice due to build status, bugs, and server issues. Remember that this is the test server, so things can, do, and will break from time to time. Check the official forums for the latest Icecrown Citadel raid testing schedule information in the weeks to come.