

He has also already filed to run again in 2028; https://thehill.com/homenews/campaign/3740578-grassley-has-already-filed-for-reelection-bid-in-2028/
Part of me thinks that Grassley might just be holding on to try and unseat Strom Thurman as the oldest ever sitting senator (Thurman made it to 100 years, 29 days).
It has Metastasised.