Constitutional Option Expiring?

The Hill reports that the Senate will adjourn the “magic” first legislative day tonight, thereby ending the opportunity to change Senate rules with a simple majority:

Under the so-called Constitutional option, on the first legislative day of a new Congress, senators can ask for a ruling from the presiding chair to amend the Senate rules and then can ratify such changes with a simple majority vote.

But senators who favor that procedural tactic for changing the rules acknowledge it’s only possible on the first legislative day of a new Congress.”

I suppose the rationale for this view would be that by adjourning without changing the rules, the Senate has adopted the old rules by implications.  But even assuming that there are senators who believe this (and Senator Merkley, at least, has stated that the rules can be changed by a majority at any time), the Senate could either continue to extend the legislative day or adopt a resolution preserving the opportunity to argue that the rules can be amended by a majority (as happened in 1975, when filibuster reformers wanted to guard against the implication that they had waived their rights).  The fact that these things are not being done indicates that a majority of the Senate is not in favor of invoking cloture by a simple majority vote.