It seems that some yogurt brands will work better than others, based on the thread here: that is new info to me, and I am excited to learn that! Because of where you live, you probably have better access than most of all to yogurt brands: would it make sense to do some comparison testing and see if some yogurts work for you?
If you spike really fast with yogurt, which seems to be the case, that probably means that somehow it is not a low GI food for you: @TiaG posted that fascinating thread recently about how it is possible that everyone has different GI calculations. If that’s true for you, you won’t need an extended bolus.
So, if you spike early, I probably would start with a regular simple bolus, but higher than usual. @Kaelan mentioned his different morning bolus: I would really look into that for you too if you take yogurt at breakfast like we do. Then, if things don’t work out by playing around with prebolus duration and with bolus ratio, I would look into extended bolus, but only if you notice that you are spiking late, for instance 2 hours after you ate.
Btw, we do a second late injection for such things as pizza, where we do get some late spiking: so we know that, for us, that is sometimes needed.