No refunds in any case.
From
https://hashfast.com/checkout/terms-of-sale:
3. DELIVERY AND QUANTITIES.
(a) Guaranteed Baby Jet Delivery Dates – Batch 1. All of the 550 Baby Jet units from Hashfast’s first production batch are guaranteed for delivery by December 31, 2013. If Buyer ordered one or more units of such Baby Jets, and Hashfast does not deliver such units by that date, then Buyer may cancel the undelivered portion of the order at Buyer’s request and Hashfast will refund the payment for the units that Buyer purchased but did not receive and cancelled. This cancellation and refund is Buyer’s sole and exclusive remedy for Hashfast failing to deliver by the December 31, 2013 guaranteed delivery date. To avail itself of this remedy, Buyer must cancel the order before such unit(s) are delivered by Hashfast, and in any case before March 31, 2014.*
(b) Guaranteed Baby Jet Delivery Dates – Batch 2. All of the 550 Baby Jet units from Hashfast’s second production batch are guaranteed for delivery by February 28, 2014. ... This cancellation and refund is Buyer’s sole and exclusive remedy for Hashfast failing to deliver by the February 28, 2014 guaranteed delivery date. To avail itself of this remedy, Buyer must cancel the order before such unit(s) are delivered by Hashfast, and in any case before May 28, 2014.
(c) Guaranteed Sierra Delivery Dates – Batch 2. All Sierra units from Hashfast’s second production batch are guaranteed for delivery by January 31, 2014. ... This cancellation and refund is Buyer’s sole and exclusive remedy for Hashfast failing to deliver by the January 31, 2014 guaranteed delivery date. To avail itself of this remedy, Buyer must cancel the order before such unit(s) are delivered by Hashfast, and in any case before April 4, 2014.
*For whatever reason it seems that this was initially "... by the December 31, 2013 guaranteed delivery date, and Buyer must cancel the order by January 15, 2014 to avail itself of this remedy. Buyer to pay all taxes, duties and shipping costs." after order completion.It was stated earlier that the explicit listing of delivery dates is HashFast's "out-of-jail" card, so to speak.
But back to the quote: even if would need to refund batch one, there are still two more months to fill batch two purchases, so I think "no refunds in any case" is slightly off.