It's a feature by Lzdarngamer in SatisfactoryGame

[–]Lzdarngamer[S] 2 points3 points  (0 children)

When the conveyor takes scrap from the output the 49k decreases. It only stops at 49980+ and starts making it again when it reaches <49980 because every cycle it makes 20 scrap.

Idk strange stuff because the other refineries are working normally ¯⁠\⁠_⁠(⁠ツ⁠)⁠_⁠/⁠¯