Yes, the warnings are removed, and do not show. But how many warnings a user has received is not removed, because the management team wants to know how good a user is. If you do not use historical, you do not see the warnings a member has received, but you still know that that particular user has been warned x times. If you want that removed, just run the following query, it will set all your user warnings to zero
Code:
update user set warnings=0
add the table prefix in front of the table name (user) if you are using one. That will reset all your user warnings to zero.