sow and mow, or mow and sow?

As a recent city escapee, i'm pretty new to cover cropping large areas. I have about a quarter acre that was an abused garden space, currently with a nice stand of buckwheat . Im planning on sowing a mix with predominantly cereal rye for overwintering, and am wondering if anyone has experience sowing rye into mulch? Buckwheat works like a charm sowed into thick mulch, but will rye make a good stand this way? anyone have experience that would hint at whether it would be better to sow into the standing buckwheat and then mow, or mow down the buckwheat, then sow?

I mowed my strip of buckwheat then hoed it under. Waited for a month, then planted potatoes. The soil was very tilthy with all that biomass. Otherwise, why don't you experiment by doing different methods and report the results?

I would sow and then mow. The mowing will create a light mulch covering your seeds and will help prevent them from being eaten by critters. It also helps them to stay moist when sprouting.