GNJA and LNV began helping OKS from the east while AMZ was still chewing up their territory. AMZ then obviously made a deal with GG as there was no fighting between them. Once the territory was cut and cities were getting rallied, GNJA and LNV were forced to drop back. AMZ is a Korean alliance with high participation and because they are all on the same time zone, their up time is loaded.
I used to rely on "an hour per tower" build or destroy, to determine my safety distance from the frontline. Now, with the speed build buff, you need to be more cautious. TP or shield for a good night's sleep.