Anacortes Army Guy

I have the Undercover Ultra Flex hardcover tri-fold on my 2020 short box, and do not have this issue - both sides lie flat. From the pictures it looks as though something on the OP's cover is bent. For the OP, when you fold the rearmost section forward and lay it on the middle section, then view it from the front, is there any obvious alignment issue between these two sections?

I just had this GM intake installed on my 2020 5.3L by the dealer, and the flash was completed as part of the install. The flash has nothing to do with the replace-air-filter interval warning on the DIC as the installation instructions tell the tech to disable that function in the DIC as it's not compatible with the non-standard air filter that comes with the CAI. On other forums there is much speculation as to the actual purpose of the reflash, but it's all guessing - an adjustment for a difference in airflow (I assume at sea level), to compensate for a difference in the new location of the MAF sensor in relation to the air box, etc., and other ideas. Who knows the real reason besides some GM tech in Detroit. As to whether or not you can get by without the reflash, one of the firsts posts on this forum is someone who installed it and encountered some issues after about a week (see below). However, I will say this, the truck feels more responsive after the intake was installed. I doubt that this is because of the negligible increase in horsepower and/or torque, but I believe it's more attributable to the reflash. But this is all seat-of-the-pants sensing, and my butt is not calibrated, so I might very well be imagining things.