When looking at a ticket the Date that the support ticket comments were posted is showing the current date instead of the posted date. as you can see the date that these posted that were made were on the 25th December not the 26th December. same with this example the ticket comments were on the 9th December yet the date stamp is saying 26th December
Please view this add-on with default style of Xenforo. I noticed that this issue may be caused by your style. You can check again.