It's not unlikely for game companies to issue ban waves during a split or near the end of a season.
These teamers usually have a goal to get a really high rank, by banning them at the end, it would mean that they wasted all their time trying to rank up, which could discourage them overall from teaming.
Though it's not something that can be confirmed, the Security Team isn't really able to let players know what they are going to do.
Those who cheat, exploit and whatnot can use any kind of information issued by them, so they can't really let anything know about future ban waves or any direct efforts they are taking.
Reporting players does definitely help, and I would recommend to keep reporting players in-game where possible.
