Krausen in Secondary Fermenter

Ok...I have read some other threads about this TYPE of issue, but I have a little more detail behind mine. (I'm a new to brewing, brewer)

Fermenting a Blonde Ale @ 67-69 degrees:
1. After 3 consecutive steady gravity readings (took 1 reading every 24-36 hours) I had my recipe target FG. (also....tasted delicious)
2. I transferred to my secondary to make room in the primary for a new batch (I know...I really need more carboys)
3. 24 hours after transferring, I have a thick krausen forming.

#3 makes me very nervous. How, after I have hit my target gravity, have I started more fermentation? I'm hoping that I don't have blow-off, but if I do, I do and there isn't anything I can do about it. My plan is to wait until the krausen is completely gone and then bottle...

Any information on why this may have happened, and suggestions to avoid this in the future?

I have relied on the threads on this site since I started researching brewing, and I'm hoping that I can once again rely on the collective knowledge of my fellow brewers. Heck, maybe the krausen isn't really a big deal, and what I think is a lot, is minimal...

I am a little low on volume too, just in case you notice.... but a fellow brewer said he wouldn't top up because you risk watering it down tooooo much... and it tastes delicious as it is..

What was your gravity ready at when you racked to secondary?

1.010

What yeast did you use? When racking to secondary you might have just roused the yeast and they got hungry again, but having that full blown krausen is really odd.

I used Belgian Witbier (Wyeast Labs #3944). I'm obviously going to just let it go...can't hurt if it keeps fermenting...right?

It looks like the little guys just woke up for a little snack when I transferred to the secondary. The layer of foam has dropped significantly in the last 18-20 hours and the beer still smells like beer, so I'm pretty sure I didn't get an infection.