Changing Calendar Views

We are looking for a developer who can create a way for our small company, to modify the display of calendars in OwnCloud.

We are currently working via Thunderbird, but Lightning is reaching its limits here, so we would like to work directly on the server.
However, the current design possibilities of the calendar views are useless for us.

We also need to make the calendars sortable.

If you are interested, please contact us via the forum, preferably in German.

If you can recommend me a Windows program/App/Web-PHP-Script, which can keep 20 calendars syncron on the desktop, then we would be very pleased about appropriate references.

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