AT Internet allows for 300 pages to be declared as objectives. By default, that number is initially set to 20. However, you can ask for more to be unlocked gradually; 40, 150 and finally 300. This is done for free upon contacting the Support Centre.
The upper limit of 300 cannot in any case be surpassed. If you reach it, we recommend deleting pages that no longer generate traffic to free up slots for newer objectives.