Lots of people will tell you "no, can't make bacon from a Kunekune"
but those same folk would probably tell you the meat was rotten and not to waste your time with them
It does take a while for them to grow to a size worthwhile for making bacon - at least a year and more commonly 14-18 months. We've made lovely bacon from Kunekunes at 18months - it was a bit fatty, but the gilts we bought were really fat when they came here and we slimmed them down a bit - but could have done with more weight off them
As long as you don't let them get too fat when growing, it should be fine though
Our 'pork' Kunes generally go off around 10-12 months old, around the 60-70 liveweight mark and we get 30-40Kg of pork cuts back. The older ones for bacon were 18 months and deadweights were 100Kg - so their liveweights would have been around 130-140Kg ish.
Because they do take longer to raise for slaughter it's not quite as easy as get in spring, send off in autumn the way you would with most rare breed weaners. But getting them spring/summer time is probably best as this way they'll get the most goodness/use from the grass and they'd be ready to send off the following year.
Only thing I would say though is that Kunekunes will need much more space than standard pigs or you will end up having to suppliment their grass ration and they will end up fatty - half an acre as a minimum for 2, allowing you to rotate too.