Can an Icchantika make any form of progress along the Buddhist path?

For those Buddhists who claim that some sentient beings are Icchantikas , do they mean that those sentient beings cannot make *any* form of progress along the Buddhist path? All I know is that, following tao-sheng, most Buddhists think that the Icchantika has buddha-nature, and that the term can also refer to Bodhisattvas, who postpone their Buhddhahood. What I'm especially interested in is whether an Icchantika can make progress toward arhatship, anything like that?