UPDATE 12/14/2017 for Hashflare.io
Estonian hashrate provider Hashflare.io is down for scheduled maintence. For more info visit their Twitter account. Hashflare.io has been a reliable provider of a good hashrate per dollar ratio and their downtime should be minimal. Tomorrow their domain name does expire (see old article below) but I doubt they are exit scamming since they have adjusted their contract length lately to match the improved profitability of their Bitcoin contracts. Likely they are making security adjustments in light of the $65 million NiceHash Hack and possibly switching some internal systems over to Segwit to try to save some money in terms of Bitcoin transaction fees.
Cloud mining provider Hashflare.io will be going down for scheduled maintenance the day before their domain expires. Despite operating for over 3 years Hashflare.io has had a lot of trouble lately updating their systems. Hashflare is facing trouble with Bitcoin withdrawals due to the increasing congestion of the Bitcoin network. To help combat this they have increased the minimum withdrawal amount to 0.0107 BTC of which 0.0007 BTC is a network fee. The Lightning Network cannot come soon enough for hashrate providers such as Hashflare and their customers. The only concerning information available is their domain name expires on the 15th of December (1 day from writing). If we assume they have their domain on auto-renewal this is likely not a problem.
All too often when the Bitcoin price skyrockets we see a shakeout of service providers. We have no reason to believe they will not resolve this issue. Click read more to view full-size screenshot of whois data and their Twitter statement from earlier downtime.