Hi,
Is NTP client mode unicast not any more availible in ROS 6.15?

It is available. Just type the ntp server in the field and it will change from broadcast to unicast.

SNTP Client broken after upgrade (NTP Clock no longer working)

I noticed that none of my v6.15 (RB400 series) SNTP Client settings for the remote (routed interface) NTP clock are not able to get the time from any of my remote time servers. As a test, I upgraded some of my other routerboards to v6.15 and the SNTP Client settings in the router OS quits working right after the upgrade.

The mikrotik that was working untill I performed an upgrade now shows in the SNTP Client setting:
Last Bad Packet Reason: originate-timestamp-mismatch
Note - this was working until the upgrade. My NTP servers (Ubuntu Linux NTP time servers) are still pingable but the Mikrotik is unable to now get the time from them.

The problem has got to be mikrotik firmware. I have other older Mikrotiks on the same network/subnet which have not been upgraded and they are able to talk to my NTP servers.

I suspect this is a firmware problem. Are there any work-arounds until there is a Mikrotik update to correct the broken SNTP Client problem ?