after i returned from inactivity the first retal i earned (when i got attacked) was not useable the samee reason Syn wrote in this thread before.
In my case an attack (not listed as counter) was not counterable 24 hours later. It was listed as available counter, but trying to attack resulted `Target is too weak for you to attack` msg. the msg included 30% PR rule.
seems like some counters expire/freeze faster than light now, while players are active and out of VM.