CRON executes CRONTABS only when run from terminal as "/usr/sbin/cron &"

[Keith Christian]

Cygwin people,

Running with this version of Cygwin.
CYGWIN_NT-10.0 DESKTOP-ASERVER 3.1.7(0.340/5/3) 2020-08-22 17:48 x86_64 Cygwin

Windows info:
$ /lib/csih/winProductName.exeMicrosoft Windows 10 Professional,
64-bit (build 18363)

I installed using cron-config, and created the cyg_server user.cron
starts OK, but does not appear to execute the crontabs.
No messages or errors  in /var/log/cron.log.

$ cygrunsrv -Q cron
Service             : cron
Display name        : Cron daemon
Current State       : Running
Controls Accepted   : Stop
Command             : /usr/sbin/cron -n

Tried these two crontab entries:

$ crontab -l
# DO NOT EDIT THIS FILE - edit the master and reinstall.
# (/tmp/crontab.33lQznXYyq installed on Sun Nov 15 11:41:55 2020)
# (Cron version V5.0 -- $Id: crontab.c,v 1.12 2004/01/23 18:56:42 vixie Exp $)
* * * * * /usr/bin/date >> /cygdrive/c/cygwin64/home/someuser/crontab_test
* * * * * /usr/bin/date >> /tmp/crontab_test

As stated in the subject line, the cron jobs execute properly when
starting cron from the terminal as "/usr/sbin/cron &"

Any suggestions appreciated.