Booking Star Alliance Return trip to Europe - how many stopovers are allowed?

I’m looking at booking a return Star Alliance flight to London from Melbourne with KrisFlyer. I see that I am able to head straight to LHR via SIN but on the return leg would I be able to go via IST and TYO using a combination of Turkish and ANA before heading back to Melbourne in a single return award?

I believe you can book the outbound flight as a Krisflyer redemption on Singapore Air metal (aircraft) and a second redemption as Krisflyer Star Alliance redemption. Depending on whether you intend to stopover (which I think you do), you have to have a better read on the stopover rules, etc. Have a read of this article.

You can now save KrisFlyer miles by adding on extra flights with Star Alliance partners