Exactly my thought
That had to be a misprint, or brass would be trashed after one firing, and it would still take a 30" barrel to get there.
Primer pockets loose?
Same powder lot?
Same bullet to lands relationship (chasing lands due to throat erosion)
If the answers are all yes, then I would certainly clean the hell out of it. It's now telling you it needs it.
130 gr bullet on a hot load might cook the barrel in 1500 rounds, but that's a big might. My .260 Rem took a nose dive around 2500 rounds.