We’ve actually figured out that that one is basically a “stutter” in your memory encoding system. Consciousness isn’t as continuous as it feels, and so you can get a situation where your memory says it just put some stuff in working memory and consciousness thinks it means your current thoughts or observations. So you end up with a feeling of a past recollection of a current awareness. Because it’s tagged “past” you can’t do anything other than understand it to be in the past, even though you’re actively experiencing it.
A related phenomenon is how you “always” wake up just before the loud noise. Even though you’re asleep you still hear things and process audio. A loud noise happens and your audio processing tells you to wake up. Conscious you wakes up, creating that new memory, and then processes the noise that woke you.

Consciousness is a process that takes place over a duration, not an instant.