This just shows that you know nothing about restocking. Pet lag occurs at the haggle page when you click on the pet to verify buying the item. It usually happens in magic and when it does happen most likely you won`t get the item because the lag will keep you at the haggle page for like 10 seconds or more then you will be brought to the Sold out page or you have bought....
It`s not normal neo lag too, because you can be browsing the whole site without lag but when you click on the pet verificiation you will then only experience the lag.