After an item is created you can always move the item to another meeting.
Go to the item screen for the subject meeting.
On the left side of the screen, find the Item Data block.
Find the meeting date. If your access privileges allow you to change the meeting, a Move to a Different Meeting link appears below the date.
Click the link to display a drop-down list of meetings in which you can place the item.
Choose the new meeting and click the Change Meeting button.