Several of us have been in this situation - although many people don't get invited for the test until after background check is complete, others get the test first. I did. It was 4-5 months after my test was done before background was completed. IRCC don't do the background check themselves so I decided to see it as a positive that they didn't think they were wasting their time having me do the test before confirming background/prohibitions! I did get my GCMS notes and they told me absolutely nothing, from which I take it that there was no 'reason' for the order, just background took a while
All to say: I wouldn't stress about the order being a little out of the ordinary. Be happy you've done your part and sit back to wait for IRCC, RCMP & all other acronyms to do theirs...
