NO.. if you have online ticket and its wl when chart is prepared, the ticket will get cancelled, so if you board the train even in general class, you will counted as ticket less.
Suppose you got PRS ticket and it is wl when chart is prepared, you are free to travel in general class with the same ticket, you may also board the reserved class and ask TTE if he could allot any tickets, he will do so if there is any...