Maintenance for the week of November 18:
• PC/Mac: No maintenance – November 18
• ESO Store and Account System for maintenance – November 19, 9:00AM EST (14:00 UTC) - 6:00PM EST (23:00 UTC)
• PlayStation®: EU megaserver for maintenance – November 19, 23:00 UTC (6:00PM EST) - November 20, 17:00 UTC (12:00PM EST) https://forums.elderscrollsonline.com/en/discussion/668861
Assuming you are on the PC/Mac (no PTS for consoles), in the launcher, click on the settings gear/circle (upper right), then check "Show Public Test Environment", then Apply. However, keep in mind, it's a separate client, and therefore a large download (30GB?). And the new version is going live tomorrow, so might not be worth doing right now unless you have very fast internet and it is truly unlimited.