§ 311.5. Amendment of the petition. 1. At any time before or during
the fact-finding hearing, the court may, upon application of the
presentment agency and with notice to the respondent and an opportunity
to be heard, order the amendment of a petition with respect to defects,
errors or variances from the proof relating to matters of form, time,
place, names of persons and the like, when such amendment does not tend
to prejudice the respondent on the merits. Upon permitting such an
amendment, the court must, upon application of the respondent, order any
adjournment which may be necessary to accord the respondent an adequate
opportunity to prepare his defense.

2. A petition may not be amended for the purpose of curing:

(a) a failure to charge or state a crime; or

(b) legal insufficiency of the factual allegations; or

(c) a misjoinder of crimes.