Maintenance for the week of April 6:
• ESO Store and Account System for maintenance – April 8, 9:00AM EDT (13:00 UTC) - 6:00PM EDT (22:00 UTC)
We are currently investigating connection issues some players are having on the European megaservers. We will update as new information becomes available.
It will apply to the attack you execute from stealth AFAIK.
Note, though, that a skill like Lotus Fan does not drop stealth, and this mechanic might apply to other skills as well. Just putting it out there.