BTW, some more numbers: 1g Fat has 9kcal. So, in order to burn 1kg fat, you need 9000kcal - but luckily, our body doesn't burn perfectly lossless, so you need ~7000kcal deficit to lose one kg.
If you stick with 1400kcal a day that's easily 500 a day defizit, so about half a kilo, or maybe two thirds. I wouldn't try losing more than two or three per months anyway, as any greater loss is hardly sustainable.
So yeah, 1400 sounds good, you should be seeing results by August if you stick with it. Caveat as I said before: If you go into "eat little mode" your body will eventually adapt and reduce your daily needs. That's why I think some more "normal days" in between are a good idea, there's even the topic of "reverse dieting" that handles this kind of issue.
