Don't worry about it. They'll see both scores, but your higher score is the only one they'll consider. Most are impressed by improvements (shows you know how to put forth an effort to overcome an obstacle), but they honestly get SO many applications, they don't think that deeply about something unless it's a big red flag. Going from 650 to 700+ wouldn't qualify as that. If anything, you might get asked in an interview how you accomplished such a big improvement, but people make large increases all the time and it's not a big deal. It's a positive, not a negative.
So...focus on your retest and getting your best score, and not what they might think of the increase. Otherwise you're needlessly pysching yourself out.