Is it ok to sow now...some seem to sow now, others in early Spring...I'm a wee bit confused :)
If you would sow spring/summer then your plants will grow large enough to start cropping during summer autumn.
If you sow now..they will be quite small to go into winter but should still over winter ok..but there would not be much to pick until the new spring growth start.
So with later sowing you only get short picking until it start flowering late spring.
I do late sowing because during summer I just don't need kale...there is so much else to eat and kale fill that 'empty' gap in spring nicely when there is only few things available. But be prepared to plant more plants than you would actually need and you can use closer spacing too. As they are not going to make sizeable plants (like with earlier sowing)and you propably loose odd one during winter too they don't need large amounts of space and being huddled together gives them bit more protection/ micro climate to withstand against the worst of the winter weather.
When you plant them in their final position..give them only one feed..enough to start them off and then nothing else until spring. You don't want them to make too much lush growth in autumn...they need just enough feed to put growth on and once its used up they need to harden off agaist the cold weather.
Many thanks for that, really helpful and clear :)