| 2022-08-09 09:25:59 | lambdacore | Updated Lambdacore as organiser of Underground Conference 2019: changed role to Network and Power |
| 2022-08-09 09:25:39 | lambdacore | Added Lambdacore as organiser of Underground Conference 2019 |
| 2021-01-23 00:16:27 | Saga_Musix | Added Scamp as organiser of Underground Conference 2019 |
| 2021-01-10 22:02:22 | docd | Added DocD as organiser of Underground Conference 2019 |
| 2021-01-09 20:46:34 | cyraxx | Added cyraxx as organiser of Underground Conference 2019 |
| 2021-01-08 15:58:05 | DJefke | Added PerfectPC as organiser of Underground Conference 2019 |
| 2019-08-20 19:39:42 | Saga_Musix | Added link http://www.slengpung.com/?eventid=722 |
| 2019-07-21 03:07:01 | FlashyLamer | Added competition Multichannel with Livesupport |
| 2019-07-21 02:51:33 | FlashyLamer | Added competition Pixel Graphics |
| 2019-07-12 15:05:47 | Bjaan | Added competition Happy Hardcore |
| 2019-07-05 11:04:20 | Saga_Musix | Added competition Shitmusic |
| 2019-06-26 21:10:04 | 100bit | Added competition Combined PC Demo / 64k / 4k |
| 2019-06-24 20:10:35 | 100bit | Added link https://files.scene.org/browse/parties/2019/uc9/ |
| 2019-06-24 20:06:17 | RufUsul | Added competition DEMOHASS |
| 2019-06-24 14:36:31 | dipswitch | Added competition Paralymp3 |
| 2019-06-22 18:23:28 | 100bit | Added link http://www.demoparty.net/undergroundconference9/ |
| 2019-04-20 19:26:19 | menace | Set invitations to fr-minus-023: Deep in the air |
| 2019-04-17 12:05:19 | Brittle | Set start date to 20 June 2019, end date to 23 June 2019, website to https://uc9.party/ |
| 2019-02-14 21:33:31 | Brittle | Set start date to 20 June 2019, end date to 23 June 2019, website to http://uc9.untergrund.net/ |
| 2019-02-14 21:33:11 | Brittle | Added party 'Underground Conference 2019' |