§ 306. Change of venue; procedure. The bringing of an action or
proceeding in the wrong county shall not be deemed a jurisdictional
defect, but the court may of its own motion and must on the motion of a
party defendant transfer the action or proceeding to a proper county.
The motion by the defendant for such relief must be made in writing and
on notice and must be filed with the clerk before or at joinder of
issue. It must specify the county to which the defendant desires the
action or proceeding to be transferred and must state under oath facts
showing that ground exists for such transfer. In the absence of timely
motion by the defendant, he shall be deemed to have waived any objection
relating to proper venue, except in the case of a real property action.

The transfer of a real property action from an improper to the proper
county may be had at any time by motion or otherwise.