Aether and Primal are geographically located in the same place so that why it affects both. There's no fixed pattern as to when L3 will be having problems which is why it will work most of the time and the at random times you'll have issues.

Unfortunately there are many posts on this by players who are affected, but ultimately it's your ISP that chooses to route you through Level 3 to get to the SE servers, this isn't something SE can change or has any control over. If you can't put pressure on your ISP to change your route (they have the technical means, they just probably won't want to), then your only options are use another ISP who doesn't route you through Level 3 or get a tunnelling service/VPN that will route you around it manually.