TCEC S17, CCC12 Both Underway

This post marks a full year since I started regularly following the two major engine-vs-engine competitions: TCEC S14 Underway (January 2019), and Chess.com CCC3 Underway (ditto). To summarize the most recent post, TCEC S17 Announced; Lc0 Wins CCC11 (December 2019):-

TCEC: The site progressed to 'Viewer Submitted Openings Bonus 12' [VSOB 12] and announced firm plans, including rules, for S17. • CCC: The CCC11 Final match ended with Lc0 beating Stockfish, +13-9=128.

Since then, both the TCEC and the CCC have started new seasons.

TCEC: After marking more time with VSOBs through 'VSOB 16', S17 started with a Qualification League (QL). The rules (see the post 'S17 Announced' for links) specified:-

The way to Div P: Season 17 will have two competitions, depending on what hardware the engines need: CPU and GPU. • The AB/CPU competition will start with a Qualification League (invitational, variable number of participants), League 2 (16 participants) and League 1 (16 participants). Promotions in the AB (Minimax, aka 'traditional') Leagues go as in Season 16. • The NN/GPU competition will have just League 1 (invitational, 16 participants max).

The 16 AB/CPU engines in the QL stage are nearing the half-way point. At least half of the engines are still in a position to qualify into 'League 2'.

CCC: In contrast to the nearly two months between the end of TCEC 'Cup 4' and the start of TCEC S17, CCC12 started less than two weeks after CCC11 finished. It uses a format not seen in any of the previous CCC seasons:-

18-engine single elimination; 200 games per match; Time control: 1|1; Opening Book: CCC12 Book (100 openings)

The brackets for the first two rounds are shown in the following diagram.

The first match 'CCC12.1: RubiChess vs. Winter' is currently underway with Rubi already having a decisive advantage.

[For further information from the various stakeholders in the engine-to-engine events, see the tab 'TCEC/CCC Links' at the top of this page. • NB: Leela = LC0 = LCzero]