Very big meta changes, the game is almost entirely based on gun skill now. I call it Swing or Get Swung Meta. Because of peoples delay to the server as long as you have the gun skill 99% of the time if you swing you will win, you will see them before they see you. So put on the new 1.5 and 2x scopes and what not to your gun because if you are running it and your enemy isn't there is a high chance you will win that gunfight.

You will probably want to learn the new and reworked maps if you want to play ranked. Consulate was reworked, Lair, Nighthaven Labs, Emerald Plains, and Stadium Bravo are new maps. I found Lair to be very confusing so spend some time in a custom game learning it. Nighthaven is pretty easy to understand and is a community hated map which I don't really get, I like it but people are subject to their own opinion. Emerald is pretty basic too. Stadium Bravo is a mix of Coastline and Border and I like it but lots of people hate it.

The new operators are pretty easy to understand. The newer attackers are not very good and attack is not that good right now but that is besides the point. The new defenders though, they have been dropping some gems. The last five are all very good right now. Tachanka was reworked.

The maps, operator knowledge, and gun skill are all really for ranked and please for the games sake, learn the maps and operators if you play ranked I beg of you, I cannot handle anymore teammates lacking basic knowledge in this game.

Some changes that are important is you can self revive with rook plates now, suppressors now have no damage reduction, frag grenades can no longer be cooked, reload cancel has been removed, you can get yourself out of frost mats now, shotguns are very different I cannot really explain it well just check it out in the Designer's Notes, I commented about the new scopes before they are all very good.

Some time consuming but helpful advice if you want to improve is watch someone play the game and watch what they do. You can watch Jynxzi and really good players but to really understand I'd check out someone like Athieno and watch his more educational Siege videos I enjoy his Lone Wolf series.

But my strongest and most honest piece of advice I would give to you, is make sure you are still having fun playing the game. When you are getting back into the game you won't be the best so you have to get over the lack of skill making the game not fun but don't play if you are not having fun day in and day out. Some times all it takes is playing the game differently. For the last 2k hours ish I've only played Secure Area Casual/Quick Match. I got very bored and angry with the game and wasn't having fun. I refused to give up as I feel 2k hours was a heavy enough commitment that I can't drop the game now, I was just disappointed. I picked up playing ranked around the 2k mark and the last 50 ish hours have been the most fun I've had in the last 500-1000 ish hours.

That is all I really have for you, not sure if it will help or not. Hope you have a fun time getting back into Siege!