Unchained Monk - access to (Quinggong) Empty Body at what level?

[jinki]

Had a look around for an answer to this but could not find one so over to those in the know for advice. :)

Under the class description for Unchained Monk, among the Ki Powers a monk can choose from is Empty Body. (I am referencing the D20pfsrd online). It does not though, have a level mentioned as to when this Ki power becomes available for selection.

Other references to this Ki power under Qinggong and Monk offer this Ki power at 20th level and 19th level respectively, and if a sorcerer was to get access to the spell Eternalness (which Empty Body references for its effects) he or she would need to be able to cast 9th level spells.

So can it be right, that as there is no level requirement mentioned in Unchained Monk that the monk can access this at 4th level?

Thanks in advance for the help.

[Rub-Eta]

As it seems, an Unchained Monk can take Empty Body as their firt Ki Power at level 4. There is no text in the original book stating otherwise. This may be an error since it mimics a 7th to 9th level spell effect.