Hi Erica, I have seen it both ways. This is a picture of winter rye broadcast spread after 2017 SB. This is the May 9th growth. We had good soil moisture and the rye was there, but a bit thin. The farmer knew his planter could do this job, so it happened yesterday.
Now, he has ~~ a week to spray glyphosate before the corn comes up. He told me that he would do a complete tank mix of glyphosate + a full season pre-emerge herbicide + 28% N.
Having said all that, I have also seen unplanted rye fields with sprayer tracks in them, in prep for what will likely be 2018 corn.
However you plan to terminate cover crops, take note, now that spring is here, the temperatures are warm and we have soil moisture: 1) Rye will jump and take off with growth from this point on – make sure that it stays manageable for your planting system; and 2) warmer temperatures and soil moisture will cause corn to emerge in a week, make sure that any glyphosate is applied pre-emerge, unless you specifically know your corn variety is properly enhanced.