Originally the text had the prepositional phrase “at this time” preceding the relative clause that it refers to. The earliest textual source, the printer’s manuscript, reads “at this time which doth await you”. (Initially in 𝓟, Oliver Cowdery wrote that rather than which, but virtually immediately he corrected the that to which; there is no change in the level of ink flow for the supralinear which. Since either relative pronoun will work here, 𝓞 probably read which.)
One can readily misread the original reading as saying that the great destruction was occurring “at this time”, which is obviously not the case since the Lord is still giving this people time to repent. The editors for the 1920 LDS edition dealt with this problem by moving the relative pronoun which forward so that the phrase “at this time” would be within the relative clause itself: “because of the great destruction which at this time doth await you”. Another possible emendation would be to move the prepositional phrase to the end of the relative clause: “because of the great destruction which doth await you at this time”. One could argue that either of these readings could have been the original; if so, there must have been some mix-up in the word order during the early transmission of the text.
On the other hand, there are a good many examples in the text where a prepositional phrase is displaced from its normal position, including a few cases where the prepositional phrase is delayed until after an intervening relative clause:
In Helaman 9:22, we seem to have the opposite problem in word order: namely, a prepositional phrase (“at this time”) belongs at the end of the relative clause (that is, “which doth await you at this time”), yet it actually precedes the relative clause (“at this time which doth await you”). It is possible that the earliest text here in Helaman 9:22 is an error. Even so, there are a few instances in the text where a prepositional phrase seems to have been moved forward from its clause, as in the following example where the prepositional phrase precedes its infinitive clause:
In Helaman 9:22, the critical text will restore the awkward placement of the prepositional phrase “at this time” before the relative clause that it belongs to (“which doth await you”); such a construction, although awkward, appears to be intended. For further discussion, see under displaced prepositional phrases in volume 3.
Summary: Restore in Helaman 9:22 the word order of the earliest extant text, with the prepositional phrase preceding the relative clause that it belongs to (thus “because of the great destruction at this time which doth await you”); although this word order is awkward and could be an error, there is evidence elsewhere in the text that prepositional phrases may sometimes precede the clauses they belong to.