I just got in touch with Hashing24 management and asked them about the promo code I have. The promo code was set to expire after June 30, 2017. When I received it, I was told that if enough hashpower was purchased with this promo code, the time could be extended or I could receive a new promo code for people to use. I e-mailed management and asked if enough hashpower was purchased using this the promo code to justify an extension on the time or possibly getting a new one. Hashing24 replied by saying "yes" and has extended time for the promo code to remain valid. The promo code will now be valid until the end of 2017 and we can continue to use it and receive 4% off our purchases. So feel free to continue to use this promo code and get some hashpower from Bitfury's cloud mining service. There are only a few good years left of some really good Bitcoin mining before all the halvings reduce to payouts significantly. Don't miss out.
Hashing24: https://goo.gl/m9QMg8
Promo Code: 35H254CH
