I'm happy to say this series has gotten back on track after the strange way volume 3 ended. Tanya has been given her battalion, and is pulling out all the stops to make her training regimen so brutal that nobody in the piles and piles of applicants should be able to finish it. But the series being what it is, it's a safe bet that things don't go entirely as planned.
The war itself has also kicked into overdrive, and the stage is set for it to turn into a truly global conflict after all. In the end, volume 4 was much more true to form than the previous one, and with the hostilities mounting, I can only imagine the difficulties Tanya is going to face from here on out.