Incubator vs. Nature Call Ducks

[urbanzoo]

Hello!! last year I ordered and hatched 4 of 7 call duck eggs I got online. Awesome experience and my duck pen made my ducks happy & quacky. Then this spring came…….!! Sooo- in mid-March I gathered some eggs (3 to be exact), put them in my incubator and thought they would be a nice addition. But since the early egg collection my girl has laid another 17 eggs in her hut. It has been decent warm temperatures during the day, 60's & 70's but a couple of nights the temperature has dropped down to the upper 30's. Based on anyone's experience-- what are the odds of these duck eggs hatching? As of today the 3 in the incubator are starting to rock around but other than to look in the hut I don't mess with mamma's eggs! She has been sitting on them every morning when I go out to feed and water and today she is a determined sitter. Also- if they should hatch do I bring them in to keep them warm for a couple of days then put them back out with her? All advice is wanted & needed!! Thanks