Sorry to hear CTRA is having troubled times. I hope it keeps going as it's the first place I look for competitive fun racing most times of day. And I'm still working my way up the licence tree!
Some ideas I had that might alleviate the situation, in no particular order:
a) have "seasons" with a week or two's break every couple of months to give an opportunity to clear any report backlogs, have a break, implement bug fixes / improvements / rule changes etc.
b) try and further automate some aspects of racing that can cause situations that lead to reports, e.g. quickly auto-spectating idle drivers, those who drive the wrong way, those who are overly slow, those who have a blue flag on their screen for more than (n) seconds - if any of these were possible it could ease the reports pressure a bit
c) open the pits later in the race for mid race joiners
d) as others have said, recruit some more assistance for report processing although maybe reducing the possibilities for report situations to occur would make this less necessary
Probably others too. Let's hope it can keep going as it's a very good framework, retaining interest in pick up racing for experienced racers whilst offering a structured introduction to sim racing for newbies.