Not certain why, but phono input cables, tone arm wires and phono preamps take a lot of use to stabilize (sound as they will long term).
New small signal tubes in well used gear can take 10-50+ hours (maybe where QS’s 30 hours comes from).
There are gizmos (for low signal strength special EQ pathways) available that help simplify the process, but I’ve never tried them (Hagerman comes to mind).
I just wait and listen to music as far as TT’s go.
Here’s a link to the $50 Hagerman gizmo that you run a line source (CD/Tuner/???) through - instead of playing LP’s.
DeKay