Chances of switching into different discussion sections at ucr / uc's in general?

Soo im not god’s favorite and ended up getting a much later time ticket to register for classes next quarter and now the discussion section i want/ most suitable to my schedule is literally about to get full. I commute about an hour and if i take other discussion sections it would give me a 6-7 hour gap :-----). What are chances of being able to attend different discussion sections despite it being full? I was able to do it this quarter for one of my discussion sections but dont know if it would be that simple all the time. I’m also a soc major by the way so