Set the Amiga clock by using a WiFi232 serial modem. Tested on an Amiga CDTV running Workbench 1.3 with a SCSI card and a BlueSCSI v1.
Requires ARexx. I used version 1.15 available from Archive.org.
From AmigaDOS, issue the command:
rx ntpwifi232.rexx
There's very little error checking being done. If you put this in a startup sequence without a modem attached, it will likely hang your system. There's also more work to be done for converting the UTC time to a local timezone.