The overview page has quite a few things that can be adjusted:
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If two plannings overlap it will be indicated by a red line. If there is spare time between two plannings it will be indicated by a dotted line.
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In timeline mode the plannings for a given user and date are displayed next to each other, and their width depends on the duration. You may also drag the left/right edge of a planning to adjust the start/end time.
Overlapping plannings are shown on multiple lines. Plannings that are fully outside the visible part of the day are indicated by an orange box; clicking on the orange box will bring up a list of planning.
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The confirmation status is indicated with a small envelope icon: red if requested, green if confirmed.
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If you move or copy the planning the confirmation status is reset.
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