My husbands boss is pissing me off!!

My husband travels all over the world for work. It's an awesome job and it provides for our family. I don't mind the travel but the further along I get the harder it gets. I'm 31 weeks also on top of that we have a 14 month old so it's been rough. He's been home a total of 2 weeks since the beginning of the year they usually don't send him out this much but since January they have been working him overtime! Now I find out that he is leaving for Siberia Russia on April 15th!! And the job may be up to 3 weeks!!!!  They know my due date and that our son came 2 weeks early! My husband has already told them he doesn't care what happens if may 5th comes and they aren't done he's leaving, but what kind of boss sends him to Siberia that close to his wife's due date?!