It is possible to move the milestone itself, and it is not so hard.
But if you have links, you need to modify their styles and implement a solution that will define the style of the link depending on its type. You can check the following example to see how it might work: http://snippet.dhtmlx.com/de8cd545f
If you add another link type, you will need to define rules for it. And I don’t have a ready solution for that.
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