How can I submit a change request through the MCP?
For reservations in "Accepted" status, making changes is done through submitting a change request. Because the reservation is now under the hotel's control, and exists in their Property Management System, all changes made need to be done in a way where a user at the property can decide if the hotel is able to accommodate the changes.
Click on the "Room Actions" drop-down, and click "Submit Change Request". You will be shown a screen where you will essentially be submitting a change request on behalf of the guest. From here, go ahead and create the change request as desired.
As you can see, you are able to submit change requests past close-down as well, because you are logged into the MCP. This does not necessarily mean that these post-close-down change requests will have a higher chance of being accepted, and in fact it's less likely since, typically, close down dates are set up mere days before check-in begins.
The ability to submit a change request past close-down really just gives you, the MCP user, the ability to continue submitting requests for guests as you see fit, while being able to stop the bulk of them from reaching the hotel at a time when they no longer wish to receive them.