is it somehow possible to get information from M-series sensor when exactly the license is going to expire? This information is not available anywhere.
As far as I'm aware the sensor does not have a license.
What will expire is your support contract that allows you to download software updates for the sensor, you can contact support for this information, they just require the serial number of the sensor.
Also, the only M-series that are going EOL are the M2750 in October 2017.