I ran 4x600 today, just two days after the time trial. I felt good, so I was aiming for 2:19/600 m. Everything went according to the plans. Splits were 2:20, 2:20, 2:19, 2:17. Recoveries were 1:11 each. (I covered 200 meters a little faster than that, then I was waiting until my watch turned 1:11, then I went on the next interval.)