I don't know is it just for me or it's for everyone - yesterday I got 3 different email messages from Freebitco.in with free WoF spins. And same thing happened today. Previously it sometimes happened that they send 2 emails per day, but 3, I don't remember such thing. Quite cool to get some extra sats/RP's or tickets.
Yes, but it doesn't happen always. It's probably because you were chosen for the bonus flash promotion, which gives you 6 hours to complete different tiers of wagering challenges, varying from 0.0005 BTC to 0.05 BTC. Each tier gives you access to higher rewards consisting in RPs, lottery tickets, WOF spins, Golden Tickets and FUN tokens. I guess you received one email, like everyone does daily, an extra one announcing the promotion, and the third one announcing the promotion has ended (after 6 hours). Each email comes with an extra free WOF spin, that is really good!
I'm saying that, because coincidentally I received that promo email yesterday, so the same may have happened to you.