The 2013 Texas Legislative Changes to Texas Family Code sec. 201.015 & 201.1042 & 201.2042 now shorten the amount of time a party has to request a rehearing from an Associate Judge's rulings. Associate Judges are typically employed for Child Support and Child Custody cases where the County and District Judges have hired a judge to sit and handle just those types of cases, thus freeing the District and County Judge's dockets for other matters. However, if you have your case decided by an Associate Judge then Texas allows you to request a rehearing, in essence a "do over," with the actual District or County Judge where your case is assigned.
The time period between the date of the hearing/order and the date you could request a hearing was the seventh working day after the associate judge makes the order and/or signs the written Order. On September 1, 2013, all cases heard and decided by the Associate Judge from that day forward will only have three working days from the date of the signed Order.
Moral of the story; file your notice of de novo appeal as quickly as possible if you want a rehearing and don't forget to specify specifically what issues you are contesting on the appeal. Conversely, if you want an associate judge's ruling to stick without hope of a rehearing, then you can always ask that the everyone waive the right to de novo appeal, which would completely cut off this option. Pro Se litigants out there, be wary of agreeing to such a request to "waive do novo."