Anyone can already sign up for testing updates.
On the future of the update function groups in PSN told PlayStation blog. Sony has already started accepting applications from users for testing the update, and everyone who passes the selection will receive 20 preview codes for distribution to friends.
In addition to increasing capacity from 8 to 16 people, Sony promised that the update would improve network performance and sound quality in voice chat.
In addition, US test participants will have early access to the text messaging feature in a mobile application using voice chat in a group.
The latter function will work only in the USA and only in English, but it is not yet possible that it will later appear in other countries.