SNTP timeout after 15 seconds but default is supposed to be 68 sec

Using sntp to query an NTP server times out after just 15 sec. Stevens-MacBook-Air:~ Steve$ sntp -d time.nist.gov Starting to read KoD file /var/db/ntp-kod... sntp sendpkt: Sending packet to 2610:20:6f15:15::27... Packet sent. sntp recvdata: select() reached timeout (15 sec), aborting. sntp recvpkt failed: -1. Server unusable on_wire failed for server 2610:20:6f15:15::27! sntp sendpkt: Sending packet to 216.229.0.179... Packet sent. sntp recvdata: select() reached timeout (15 sec), aborting. sntp recvpkt failed: -1. Server unusable on_wire failed for server 216.229.0.179! According to sntp documentation and man page for sntp, default is supposed to be 68 seconds. Is this a bug sntp installed in OS 10.11.6?