Mo. Rev. Stat. § 508.160
Current with changes from the 2023 Legislative Session
In all cases of application for a change of venue, all pleadings shall be filed and the issues made up before the entry awarding the change is made; but after the change of venue, any pleading found insufficient upon demurrer or otherwise may be amended as in other cases.
§ 508.160, RSMo
RSMo 1939 § 1064, A.L. 1957 p. 294