they were frozen and closed if opened on a sketchy visa via an agent. If you been working legally and retain a few bank accounts for many years after switching nobody will take them away from you. They reissue cards even if you come back on a stamp and had your accounts dormant for quite a while..
Operating a business is kinda implied there๐ and you can't legally oversee/operate it on DTV as it's considered work.. I'm not trying to discourage anyone, just know your risks beforehand. Otherwise one may end up paying very high "fees" or being booted out (or both actually)