If the job posting on the CG website closes on the end of the month for example, does that mean HR will wait till then to only start processing and shortlisting interviewees.

Or if let's say the job posting closes on the 20th July, then I apply on the 17th July (so very close to the end date) does that it is possible that they have already shortlisted candidates and might have chosen someone for the job. So the chances of me being shortlisted is low because there might already be someone selected for the position. Does this make sense?