Entering a value greater than 0 will inject a cookie in the visitor's browser to tell our system the the visitor has arrived from a bypassed domain or IP address.
This will ensure they are not redirected again if they visit your website directly.
Example:
Your website website.com is setup to redirect Canadian visitors to website.ca.
However you also have links in the Canadian website that goes to website.com.
By adding the domain website.ca into the list of bypasses, if a Canadian visitor browsing on website.ca clicks on the link to website.com, they will not get forced redirected back to website.ca.
In the bypass example above, if a cookie time is used, then the visitor (from Canada) can directly go to website.com again without getting forced redirected to the website.ca.
Cookie time is entered in hours and there is no limit on the number of hours that can be entered.