Ferrin had not been paid for four months, the sports daily Jornal dos Desportes said, and spent Monday in discussion with the Angolan Football federation while his squad headed to the south of the country to begin their training.
A 25-man squad, excluding the country's European-based contingent, will spend the next three weeks at altitude in Lubango and play warm-up internationals against Gambia, Cameroon and Rwanda.
Ferrin's future was unsure, the newspaper added, suggesting that he might be on the verge of departing. The Uruguayan signed a two-year deal in July.
Angola open their Nations Cup campaign in Johannesburg on Jan. 19 against Morocco. They meet hosts South Africa and the Cape Verde Islands in their other two Group A matches.