Ubisoft have posted their plans for Y3S3 patch in Rainbow Six Siege that is due on 18 September 2018. The new patch includes a description of new punishments for team killing in both Casual and Ranked queues, which will now be the same.
This will be the first patch in Rainbow Six Siege since the release of Operation Grim Sky and most of the changes will be actually fixes to the revamped Hereford Base and the new operators - Maverick and Clash.
The most notable change will be to penalties for team killing, since they were confusing to players according to Ubisoft. Killing a teammate in Casual would kick the player from the game and while the same would be done in Ranked, the player would also be banned from matchmaking for 30 minutes.
Penalties will now seemingly be standardised and the first team kill will warrant a 30 minute ban in both queues, growing to one hour for the second team kill and two hours for third. Should repeat offenders persist in killing their teammates, they will be banned for 24 hours for the fourth kill or one week for five kills.
There is currently no explanation when the team kill counter resets or how much time needs to go by for it to happen. It would be rather silly if someone killed five teammates over the course of two weeks in legitimate friendly fire and then got banned for a week. That said, this will likely not be the case, it is just that Ubisoft didn't disclose the full behaviour of the team killing punishment system yet.
When it comes to the fixes, Hereford map prevented players from deploying gadgets on the outside in some scenarios which has been mended with the new patch. As far as operators go, Maverick received one fix regarding the trajectory of the ejected bullet casings while firing the AR-15.50.
Clash proved to be a bit more problematic so she has six fixes scheduled in this patch. You can read all about them, as well as other miscellaneous fixes on the official Ubisoft announcement.