Interview emails to candidates going out in wrong time zones

Content

I scheduled interviews with candidates for this week and the interview has CST and me as the user is set as CST and the interviewers are all set as CST. This is something I do all the time and never have problems. However, today the interviewer and me as the scheduler has the correct time as CST but all the candidates recieved emails that has GMT a European time zone! After scheduing over the phone and setting up the times with the candidates and confirming, now they are gettting email with times 5 hours off! Please help!