After Destiny Update 2.3.1 launched on Tuesday, numerous reports from players popped up that they were receiving BEAVER error codes, which caused complications regarding NAT settings. Bungie began investigating immediately, and suggested you keep your personal NAT Open in the meantime.
In a new status update, Bungie announced that they’ll be releasing Destiny Update 2.3.1.1 today on PlayStation 4 and Xbox One to address the BEAVER issues:

Patch 2.3.1.1 will go live today for PlayStation 4 and Xbox One to alleviate ongoing BEAVER errors. PS3 and 360 updates coming soon.

Here’s the official patch note for the hot fix:

Technical

Fixed a network connectivity issue that was causing some players to be disconnected with BEAVER errors
2.3.1 was the last planned update for Destiny on PlayStation 3 and Xbox 360, but Bungie said they’d still release “emergency fixes for future game-breaking issues.”
Bungie also offered an update on the latest Nightfall issue:

Destiny Player Support is aware of reports that players are not receiving strike specific loot upon defeating the final boss of this week?s Nightfall Strike. Nightfall Post Game Carnage Report Rewards are NOT impacted by this issue, nor is the Vanguard Heroic Strike Playlist. We have forwarded reports to the appropriate party for investigation, and will provide updates when available.

Have you been experiencing the BEAVER error code since Tuesday"
[Source: Bungie (1), (2), Bungie Help]
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