Expect to see plenty of censorship news coming out of China over the next week.

The country’s National Congress is a hugely influential political summit that takes place every five years, and includes the selection of central party leadership. It is also a time when Chinese censors are on high alert, particularly when it comes to online media.

The next summit, the 19th, takes place on Wednesday, and is likely to last around a week. Already, on the eve of the gathering, we have the first glimpse of internet restrictions for Chinese users.

WeChat, China’s top messaging app with more than 800 million registered users, has prevented its users from changing their nickname, profile photo or tagline until the end of October, as noted by WeChat expert and ChinaChannel blogger Matthew Brennan.

It may seem subtle, but it is a move to prevent the spread of political ideas and opinions that Beijing would prefer kept silent through user profiles and alias updates, a common form of expression that reaches beyond a single conversation.

Eve of the 19th party congress: WeChat suddenly announces users are blocked from changing avatars, nicknames and taglines till end of month pic.twitter.com/QoEMnY1eyF — Matthew Brennan (@mbrennanchina) October 17, 2017

That’s not likely to be the only piece of censorship rolled out on WeChat. The company has long self-policed its users by blocking specific sensitive words in response to government demands to take responsibility for user content, but it is harder than ever to detect. That’s because last year WeChat quietly removed a setting that informed users when a word they used was censored.

WeChat will not be alone in clamping down, though. Expect Weibo, China’s top social network, among others to impose limitations.

Weibo blocked photo uploads from users around the anniversary of the Tiananmen Square massacre in June and last month it gave users a final deadline to verify their identity. That’s a key tactic that helps the government clamp down by making users directly accountable for their content, and it explains why “anonymous content” in general is banned on the Chinese internet.

Elsewhere, WhatsApp may be impacted once again as it is seen as a popular channel for dissidents and activists. The service suffered interruptions in September after it was heavily used following the death of dissident Liu Xiaobo, a recipient of the Nobel Peace Prize, who lost a battle to liver cancer after been denied permission to leave custody to seek medical treatment overseas.

Airbnb is another foreign company that has been impacted by the upcoming congress after it removed all availability in Beijing during October.

“Due to external circumstances, homes in certain areas in Beijing are unavailable through October 31,” the company told Beijing-based hosts last week, according to Reuters.

These disruptions are just the tip of the iceberg. Beyond long-term blocks on Facebook, Twitter, Google and other Western internet services, China has increasingly cracked down on freedom of speech online in recent years under President Xi Jinping.

Most recently, pressure from the government led Apple to remove VPNs, services that help circumvent China’s “Great Firewall” internet censorship system, from its App Store in a move that drew criticism from many quarters. The Chinese government has continually placed limits on VPNs, going as far as to ban them from hotels and force any remaining providers to apply for a license in order to operate.