The excessive number of reps at heavier weights you did on the way up would be the prime suspects. If you want to do a heavy single at 440, which may not be the best choice given your disrupted training schedule, don't do a set of 5 at 350 and a triple at 390. I feel like you may have been able to stand up with that 440 if you had really wanted to do so and had chosen your warumps appropriately.
You need to go deeper on most of your squats. Getting your knees out a little more might be all that is needed to make that happen. Tough to say for sure since we are far off to the side.