[Newsguy]

That is exactly the point.
They say the replacement is only good for a specific interval.
From LN:
Roller bearings, like ball bearings, will have service intervals, requiring future replacement, even if manufacturers claim otherwise. The only IMS replacement that is permanent and does not require future servicing is the IMS Solution which is based on the oil pressure fed plain bearing design used by Porsche for the Mezger engine's intermediate shaft.
And:
It is best practice to replace the IMS bearing as part of regular preventative maintenance. Depending on what bearing technology is used, service intervals can vary greatly, with the IMS Solution's oil fed plain IMS bearing is considered the best solution to prevent IMS bearing failures.
Personally, I prefer one and done.
I'm deep enough in this engine that I do not wish to be doing this work again on a regular basis.