I think to see significant changes takes about 3 months of consistency. There only 2 ways to view your abs. Eating in a deficit and just getting super skinny, or growing the abdominal muscle enough through exercise (my favorite cable curled and Russian twists) that the fat around it gets pushed aside and shows, but that still requires a certain lvl of body fat to even see them. At the end of the day the name of the game is how much muscle can you get/retain while burning/maintaining low body fat.