This notice went out in an e-mail to API users today:
Next week, the Microsoft adCenter API Production environment will undergo planned system maintenance, October 23 through October 26 in preparation for the adCenter Fall Upgrade. Although there will be no downtime, and your ads will continue to serve, there will be some delays to the editorial processing of ads and keywords. We recommend that you do not make any changes to your ad text or keywords during the maintenance. Instead, load all changes through the API by October 23.
Note All other API functionality will continue to operate as expected during this maintenance.
We'll be posting more information to the blogs about the adCenter Fall Upgrade. Also, watch for an e-mail next week about how you can try out the new adCenter API features in the Sandbox+ environment.
If you have any questions, please post to the forum or contact our API Support Team.