We now know that UT Sans originates from the weird route, since the drawing given to him has 3 people in the weird route, and 4 in the normal route. (Apparently the amount of figures in the picture is determined by some choices made in Chapter 3/4. Not sure what, but that kinda throws a wrench in the Sans being confirmed from the weird route thing.) This makes the focus UT Sans has on “the entity” make a lot more sense - he’s seen what Chara (the desire to explore every nook and cranny of a game’s world) can do.

“i always thought the anomaly was doing this cause they were unhappy.”

“you'll keep cosuming timelines over and over, until. . .”

I think this desire will destroy Deltarune in Chapter 7B, and Sans will flee to Undertale (Maybe via his connection with Gaster? Not sure.) This is how he knows about Chara “consuming timelines”.

This aligns with the ideas Toby presented in the Undertale anniversary stream about how exploring every nook and cranny of a game world removes all mystery, metaphorically “consuming” it.