With my first I started epo, I think, at 36 weeks. I started by taking 1 cap orally until 37 weeks. I think dosages vary (500, 1000, 1300, etc). I believe I had the 1,000.
At 37 I started inserting one. Then I think at 40 I started inserting 2.
Labor didn't start for me and was induced at 41+6. I don't know if epo helped or not, but by the time I was induced I was 3-4 cm dilated and 100% effaced.
This time I started orally at 34 weeks (1,300). Started inserting 1 at 36 weeks and 2 at 37 weeks. I don't know if I'm effaced any, but am dilated 1 cm as of Thursday evening (38 weeks).
Oral can be taken any time of day. If you insert, insert right before bed and wear a liner as it'll probably leak.