As of February 6, 2019, Amadeus GDS users are able to process voluntary ticket refunds of TAP tickets through Amadeus ATC Refund, a fully automated refund calculation tool.
By eliminating the risk of errors and consequently the number of ADMs, in two steps the tool calculates the values of fare and taxes to be refunded, as well as, verifies any penalties.
Travelport and Sabre will be developing a similar tool. For more information please contact these GDS.