C. F. Keil and Franz Delitzsch on Esther 9:28

Est 9:28

And that these days should be remembered and kept throughout every generation, every family, every province, and every city; and these days of Purim are not to pass away among the Jews, nor their remembrance to cease among their seed. The participles ונעשׂים נזכּרים still depend on להיות, Est 9:27. Not till the last clause does the construction change in להיות לא to the temp. finit. יעבור ולא is a periphrasis of the adverb: imperishably, inviolably. כּכתבם, secundum scriptum eorum, i.e., as Mordochai had written concerning them (Est 9:23). כּזמנּם, as he had appointed their time. מן סוּף, to come to an end from, i.e., to cease among their descendants.