IBM did it before, making an unannounced Technology Refresh for IBM i 7.3 in the spring of this year, TR12. I have been informed that they have done it again releasing another unexpected TR, TR13, on December 1.
Perhaps I should not be surprised. IBM i can now be run on a Power10 server. Could these PTFs fix compatibility issues there? Could they be updates for security fixes as well? Only IBM knows.
You will find all the details for this TR PTF on this page: SF99727 730 Technology Refresh – level 13.
