You will get a better response to backloading if the backload is done an hour and a half after the workout. The more time that passes, the more insulin resistant you become. That being said, you still get results. Just make sure you wait until the end of the day to consume your carbs.
I typically work out late morning to early afternoon and I backload at night. (which is the only time to backload) But there is a definite difference by working out later in the day and then slamming a huge backload at dinner time and beyond for the rest of the night. The closer to the workout the backload is, the more you're going to get funneled directly into your muscles with the least amount of spillover into fat cells.