Ann: Trading Halt, page-42

You are better off doing your own reading into it for more detail. The subject has come up on HC a few times over the last 3 or so years since I invested. I'm sure they are serious enough but Cabinda has too much oil so there is no way Angola will allow its independence.

"Adjacent to the coast are some of the largest offshore oil fields in the world.[7] Petroleum exploration began in 1954 with the Cabinda Gulf Oil Company, when the territory was under Portuguese rule.[8]Cabinda also produces hardwoods, coffee, cacao, rubber, and palm oil products; however, petroleum production accounts for most of Cabinda's domestic product. Cabinda produces 700,000 barrels (110,000 m3) of crude oil per day.[when?] Cabinda Oil is associated with Sonangol, Agip Angola Lda (41%), Chevron (39.2%), TotalEnergies (10%) and Eni (9.8%).

https://en.m.wikipedia.org/wiki/Cabinda_Province