Sonarr randomly picks up torrents for whole (monitored) shows, but I never initiated the search

Sonarr version (exact version): 3.0.8.1507
Mono version (if Sonarr is not running on Windows):
OS: Windows 10 (64-bit)
Debug logs:
2022-08-03 01:31:41.2|Info|RssSyncService|Starting RSS Sync
2022-08-03 01:31:54.5|Info|DownloadDecisionMaker|Processing 101 releases
2022-08-03 01:31:54.8|Info|RssSyncService|RSS Sync Completed. Reports found: 101, Reports grabbed: 0, Reports pending: 2
2022-08-03 01:47:11.6|Info|RssSyncService|Starting RSS Sync
2022-08-03 01:47:24.9|Info|DownloadDecisionMaker|Processing 101 releases
2022-08-03 01:47:25.3|Info|RssSyncService|RSS Sync Completed. Reports found: 101, Reports grabbed: 0, Reports pending: 2
2022-08-03 02:02:42.0|Info|RssSyncService|Starting RSS Sync
2022-08-03 02:02:55.3|Info|DownloadDecisionMaker|Processing 101 releases
2022-08-03 02:02:55.7|Info|RssSyncService|RSS Sync Completed. Reports found: 101, Reports grabbed: 0, Reports pending: 2
2022-08-03 02:18:12.3|Info|RssSyncService|Starting RSS Sync
2022-08-03 02:18:25.7|Info|DownloadDecisionMaker|Processing 101 releases
2022-08-03 02:18:26.1|Info|RssSyncService|RSS Sync Completed. Reports found: 101, Reports grabbed: 0, Reports pending: 2
2022-08-03 02:21:48.3|Info|Auth|Auth-Unauthorized ip ::1 url ‘http://localhost:[port]/sonarr/api/series’
2022-08-03 02:21:53.4|Info|Auth|Auth-Unauthorized ip ::1 url ‘http://localhost:[port]/sonarr/api/series’
2022-08-03 02:21:58.4|Info|Auth|Auth-Unauthorized ip ::1 url ‘http://localhost:[port]/sonarr/api/series’
2022-08-03 02:22:03.5|Info|Auth|Auth-Unauthorized ip ::1 url ‘http://localhost:[port]/sonarr/api/series’
2022-08-03 02:33:42.7|Info|RssSyncService|Starting RSS Sync
2022-08-03 02:33:56.0|Info|DownloadDecisionMaker|Processing 101 releases
2022-08-03 02:33:58.7|Info|DownloadService|Report sent to Deluge. Veep.S07.1080p.BluRay.x264-ROVERS[rartv]
2022-08-03 02:33:58.8|Info|DownloadService|Report sent to Deluge. Veep.S01.1080p.BluRay.x264-ROVERS[rartv]
2022-08-03 02:33:58.9|Info|DownloadService|Report sent to Deluge. Veep.S05.1080p.BluRay.x264-ROVERS[rartv]
2022-08-03 02:33:59.1|Info|DownloadService|Report sent to Deluge. Veep.S06.1080p.BluRay.x264-YELLOWBiRD[rartv]
Description of issue:
I’m slowly rebuilding my library, so I have a ton of monitored series, but I have been initiating the searches manually. Occasionally, I’ll find a whole show’s worth of torrents in my torrent client that appeared overnight, but I never initiated the search. Yes, the series is monitored, and I understand newer episodes will still download, but what is causing whole (Ended) series to randomly be searched?

It’s doing what it is supposed to. It’s not being randomly searched. Anything that appears in an RSS feed that is wanted will be grabbed.
Series is monitored. Anything that is missing from that series is considered Wanted.
Series pack appears in RSS feed because it was just posted/reuploaded.
Sonarr grabs because it is wanted.

Sonarr is not doing any searching there and generally doesn’t search on its own.

faq entries and quickstart guide explain how it works
https://wiki.servarr.com/sonarr/faq#how-does-sonarr-find-episodes

2022-08-03 02:22:03.5|Info|Auth|Auth-Unauthorized ip ::1 url ‘http://localhost:[port]/sonarr/api/series’

What on your device is accessing sonarr without a valid apikey and trying to use the legacy depreciated api route?