Bombardier (BBA, Montréal Trudeau) has revealed that C-Series launch operator, Swiss (LX, Zurich), has converted ten of its thirty firm-ordered AC?CS1s into larger AC?CS3 variants.

The Lufthansa (LH, Frankfurt Int'l) subsidiary's original order with the Canadians was placed in 2009 and consisted of thirty CS-100s.

Last month, Bombardier announced Swiss Global Air Lines (LZ, Zurich) would become the C-Series' launch operator after Sweden's Malmö Aviation (TF, Malmö) withdrew from the position in September last year.

Should all things go according to plan, the first CS100 is slated to enter revenue service with Swiss during the first half of next year.