dvs7310

Because your trips are spread over two calendar years, you want to find a program with a rolling validity based upon your qualification date rather than the Dec 31/Jan 1 cutoff.

I don't know which system Voyager uses, however unless you live in South Africa I probably wouldn't use them. Getting miles into Voyager aside from flying is nigh on impossible without access to a credit card from a South African bank. Unfortunately they do not partner with American Express & Diners Club (in most countries at least), nor SPG for mileage transfer.

Because you're flying business class already, the additional benefits from Star Alliance Gold are minimal, basically you'd have one additional piece of luggage allowed, so don't go too far out of your way to status match in advance.

If you think you might like to dump some additional miles into whichever program you chose to make an award booking, have a look at which credit cards you have access to and which programs those points can transfer. Amex Membership Rewards, Diners Club, and SPG are typically the most versatile, however Chase and Citi in the US are now becoming a lot more useful as well as both are adding more airline partners.

If I were in your situation I'd probably be looking mostly at A3 (Aegean). Your SA flights in business will credit at 200%, they have a fairly easy qualification for Star Alliance Gold, and their mileage chart for redemption is fairly good. You can transfer SPG points to them as well if you have access to a SPG credit card (or stay in SPG hotels a lot).

Miles and More also credits at 200% but their qualification bar for Star Gold is really high, that wouldn't be a problem if all of your flights were in 2018 but they use the calendar year system, therefore you'd reset on Jan 1 and wouldn't make Senator. Asiana's program is also pretty attractive with a low qualification threshold and a 2 year validity, but they only credit SA business at 125% and they don't have a really sexy award chart.

If you want maximum validity then you may still want to consider Asiana, you'd end up with about 90,000 miles after all is said and done and that would give you *G for 2 years. Otherwise A3 gives you a lot more miles to use (~142,000), but it's only a 1 year qualification.