Internal job post. Applications after closing date?

So my employer listed a job on the internal recruitment website; for a position which i applied; I know for a fact I am the only one that applied before the closing date advertised alongside the job.

So yesterday I recieved my confirmation date and time of interview along with the others who applied after the closing date. Is this allowed?

I am now considering removing myself from this position due to the fact the people applying have somewhat of a close connection to the interviewer.

any advice?