I recently sent my Debut bearing to A.J. for servicing.
It is 10+ years old.
He took it apart, applied a micro-hone technique, updated the thrust configuration and sent it back for not too much money.
He also checked over the platter concentricity when mounted on the bearing.
Now the bearing is UTD and works like a charm. Dead Quiet!
Factory service or change your own oil? On something this high performance it seems sensible to me to have it looked at by the manufacturer. Oil is not the whole picture at all.