Volontary fasting rewards and tavelling

**As-Salam Alaikum** I was wondering, if i do a voluntary fast (ie. not Ramadan) and due to traveling i would break the fast temporary for the travel time (ie more than 3 hours). Then resume the rest of the day, would i still get the reward for fasting that day? I did try to find somethings on it, but most of the information is on Ramadan fasting and it is generally good to makeup a day of obligatory fasting. But since this is a voluntary fast i wondered if it carried some of the same rulings? > source would be gladly appreciated. Also if this question falls too much into a grey area where more doubt can arise than certainty, let it go into the dark where it belongs.