I will retest the JSON code to see if anything in the latest release has caused problems. It does appear that your module has not had a chance to synchronize it's time with a gateway. This is done once a day. I will look and see if there is a need for some retries to improve this function.

There is no official DateTime format for JSON. We have chosen to support the ISO 8601 format. This format has a few acceptable representations. We have chosen to support 3 of them:

YYYY-MM-DDTHH:MM:SSZ -> This is Zulu time or UTC time.
YYYY-MM-DDTHH:MM:SS -> Local time without time zone information which is not very useful unless you are talking to only services in your local time zone.
YYYY-MM-DDTHH:MM:SS+HH:MM -> Local time with time zone information.

The JSON string conversion is by default done using the local time with timezone information. At this time there is no way to tell the JSON class to use another time format. You can however convert a DateTime object to a string using .ToString("L") or .ToStirng("Z") to force local time without timezone or Zulu time representation. You can then add your string to your JSON object.