After years under a previous regime, several prominent Internet piracy groups have adopted a new set of TV-release standards. The rules will go into effect this weekend, but several groups have already made the switch, frustrating many bewildered pirates who must now play .MKV instead of .MP4 files.

While pirates may not appear to be the most organized people, the groups that make up the top of the piracy pyramid abide by strict rules.

Every so often they agree on a new set of standards, which determine what a proper release should look like. Most recently, new changes were announced for TV show releases, and these are set to go into effect this coming weekend.

The new rules are announced in lengthy documents, one for HD and one for SD TV-releases.

“Since the last revision of this document in 2012, TV-X264-SD has grown and become a major section that many people contribute to and depend on. This new revision aims to update the standards from 2012 to standards suitable for 2016 and the future,” the intro to the SD version reads.

The rules are intended for Scene groups only. These groups don’t share their work directly to the public, but between themselves on so-called “topsites”. However, most of the time their releases are also the source of TV-shows that end up being shared on public pirate sites.

This means that hundreds of million of people around the world will be affected by the changes, albeit indirectly.

For the most part the rules deal with technicalities regarding release formatting, tagging and various audio, subtitle and video settings. These changes are hardly noticeable to outsiders, except for the “container” part.

Instead of using .MP4 as the file format, all releases will be .MKV moving forward. This is the Matroska container which has been the standard for HD releases in recent years.

Some groups have already made the switch over the past few days, causing confusion among BitTorrent users.

“SUDDENLY everything (well many things) is MKV instead of MP4,” one downloader writes, adding “There is no way a way a whole bunch of encoders woke up today and suddenly decided to use MKV instead of MP4. Does anybody have any idea Whats going on?”

Others complain about not being able to watch MKV files on their video players, or branding MKV as inferior.

“All I can figure is that since things were just fine the way they were, a couple of people decided to screw everything up for everyone else,” another frustrated TV fan notes.

Several P2P TV-distribution groups, which are not part of the Scene, were also taken by surprise. However, TorrentFreak is informed that they won’t convert their releases to MP4, as some people have recommended.

Instead, the ETTV group advises TV-show downloaders to convert the videos to MP4 themselves if they want, pointing them to the free Rebox tool that can do this in a few seconds.

“SD tv shows will soon be released in mkv containers. If you’re an mp4 fan you can remux the mkv files to mp4 in 2 simple steps in less than 30 seconds with the app link below,” ETTV writes.

Interestingly, there were also massive complaints in 2012 when the SD standards changed from .AVI to MP4. At the time some people were literally outraged, vowing to ban certain sites and groups.

Whether we will see a repeat of this backlash will become clear after April 10, when the rules go into effect.

This time around it may not be as bad. Many video players support the MKV format and a lot of downloaders were already familiar with it, since HD shows have been released this way for years.