We tried solving the issue only through software updates, and for a while we did, but the intensity of the attack is growing by the day and the current clearnet VPS is way too weak and cannot handle it. We will upgrade to a much bigger dedicated server and we expect the issues to be solved at least to a certain degree after that.
From what I've read about DDOS-attacks, home-made solutions are futile. Theymos
gave up years ago. It's very expensive to mitigate, while the attack (using a botnet) is very cheap to run.