Reply To: No 2-4-1 yet, but flights available – can I book then apply a voucher later?

[AJA]

Short answer is no. But you could book the trip as two one ways and use the 2-4-1 when you have it to book the return.

To book and add the return you have to use the 2-4-1 to book the outbound at t-355. You cannot apply the 2-4-1 retrospectively in any other circumstances