How to upgrade from 2.0.3. to 3.1.2

Hi,

I want to upgrade from Docman 2.0.3 to 3.1.2

I run a Joomla 3.8.1 and my docman is not working. I'm getting the following entries in my error.log file, which I understand that is due to my version of Docman being not suitable for my version of Joomla.

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[21-Oct-2017 12:40:23 Europe/Berlin] PHP Fatal error: Call to a member function get() on a non-object in /home/isatapsy/public_html/administrator/components/com_docman/model/abstract.php on line 365 [21-Oct-2017 12:40:45 Europe/Berlin] PHP Warning: Invalid argument supplied for foreach() in /home/isatapsy/public_html/templates/j51_ashley/php/styles.php on line 137 [21-Oct-2017 12:41:00 Europe/Berlin] PHP Warning: Invalid argument supplied for foreach() in /home/isatapsy/public_html/templates/j51_ashley/php/styles.php on line 137

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I see in your upgrade instructions how to upgrade from:

DOCman 1.x to DOCman 2.1
DOCman 2.0 to DOCman 2.1
DOCman 2.1 to DOCman 3
DOCman 3.0 to DOCman 3.1

Does this mean that I cannot upgrade directly from 2.0.3 to 3.1.2, and that I have to run all those intermediate upgrades inbetween?

Thanks in advance for your reply.

Regards,

Juan