I just checked and see that my 64sx is at 2.30. Not sure when that was done, the last time I connected it Garmin Express said I was up to date. I don't see any difference in how it operates.
The GPSr should have prompted you that a new update was available when powering the unit on and allowed you to decide if you wanted to install it now or later.
Do you not remember seeing that screen?
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