Unfortunately, RV owner guides are not generally well written and omissions and inconsistenceies are common. Don't be surprised as you find others - or find that you are simply unable to answer seeemingly simple questions by referring to your manual.
Does your coach have automatic leveling? If so, it is possible that "air dumping" is automatically done as part of the automated leveling process. This is especially likely if the leveling is done primarily with the air suspension, but may be part of a hydraulic jack leveling system too. But I suspect you would already know if that was happening...
You could ask your dealer but they are notorious for incorrect information. All too often dealer personnel often give their personal own opinion of the answer rather than the factory-specified one. A call to Holiday Customer Service is your best bet.
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL