I definitely think you're right as long as the company is who gave him the warning. A lot of companies do not want a driver to create an off-duty log that crosses into another month. However there is not a FMCSA rule that states a driver cannot log an off-duty log that crosses into another month. The company is only required to keep the logs for 6 months, they usually file the logs into single months and trash them as they become older than six months. Having an off-duty log that spans from the 7th month (trash) and the 6 month means they wouldn't be able to throw it out, or might accidentally get thrown out.
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