even manual players get flagged. if you are legit or bot the result is the same if you make games too short and dont add any delays before making a game.
if you use a vpn expect 2-3 weeks of ip restriction = "unable to connect solid box" and you cannot log in.
if you are ip restricted due to too many games you will get "checking versions dialog box" and you cannot log in
sometimes instead of getting the checking versions error you will get wait in line. there is a max number of games per cdkey/ip and if you go over you can expect a c/i then get booted from d2 for around 10-20 minutes. when you log back in you will be wait in line for about 2-3 million seconds. 60 seconds×60 minutes×24 hours = 86400 ( 1 day ) x 24 = 2073600
another thing that can cause an ip restriction is player abuse and spamming text in game too fast. to reduce the risk of this i try not to type in game and use the lobby. its also keyword based so avoid anything that is a known item site or include .com
you should have a backup set of cdkeys and accounts with a different email and different ip. dont allow any account email cdkey ip to cross contaminate the other accounts, use backup accounts as needed and allow main ip accounts cdkeys to unrestrict.