Question
If the AUP expires, will the Solution stop working?

Answer

When the Annual Upgrade Protection (AUP) expires, you are no longer entitled to download and install updates and upgrades for the solution. New upgrades and updates for the solution will not work with solution's license. If you download and install an update or upgrade for a solution and the AUP is expired, the solution will not work properly.

Most solutions continue to function normally when the Annual Upgrade Protection (AUP) expires, but must not be upgraded if AUP is not in effect. Purchased licenses don't expire, but when the AUP expires, you shouldn't  upgrade the solution to a newer version (released after the AUP expiration date) because updates installed when you are out of the AUP period, won't work with your existing solution licenses.

When AUP is expired, you are not entitled to those upgrades and while you may be able to download and install them, upgrades made available after the AUP is expired won't work with the licenses you purchased unless the AUP is renewed.

When AUP has expired, Patch Management Solution's pre-existing software bulletins will be available for enablement and deployment of their related software updates. The Notification Server will no longer be able to download updated versions of the PMImport.cab file. Software update policies and inventory rule scans will continue to function. However, it will not be possible to obtain updates for new bulletins and their corresponding inventory rules due to the inability to update the pmimport.cab. If a newer version of the solution is installed, it will not function.

Other Solution's functions continue to function normally when AUP is expired.

"Altiris licensing technical FAQ"  (KB 178715)