If I understood correctly, the question is now to calculate the today + 1 month day. The answer is:
date.setMonth(date.getMonth() + 1);
On a side note, I would like to remind you that this question is not directly related to Kendo UI and as such is out of the scope of our support service. The knockout library, as well as knockout-kendo framework are not developed nor maintained by the Kendo UI Team. Any support requests (via tickets or forum posts) should go to either StackOverflow, or to the issues list for that project.
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