What happens with a 0-day buffer entered?

The internal target and external deadline become the exact same date, and the receipt notes directly that no buffer separates them.

Does switching between business days and calendar days change which dates are solved?

Yes, a buffer of the same numeric size resolves to different actual dates depending on which mode is selected, since business-day mode skips weekends and any entered exclusions while calendar-day mode counts every day.

Deadline Buffer Planner

Keep your own internal target separate from the external deadline you've committed to, with the buffer between them always shown.

Worked example

An external deadline lands on Friday, January 8, 2027. With a 3-business-day buffer, the internal target works out to Tuesday, January 5, the point by which the actual work should really be finished, leaving 3 full working days of slack before the real deadline. Switch that same 3-day buffer to calendar-day mode instead, and the internal target shifts to Tuesday, January 5 as well in this case, but a longer buffer crossing a weekend would land on a different date under each mode.

Common mistakes

Treating the external deadline as the actual working target, which erases the buffer entirely the moment anything slips even slightly.
Mixing up business-day and calendar-day mode when comparing two buffer plans. The same numeric buffer size resolves to different dates under each mode.

Limitations

The buffer is whatever number is entered directly. This does not estimate risk or suggest how large a buffer should be for any specific project or deadline.

Frequently asked questions

What happens with a 0-day buffer entered?: The internal target and external deadline become the exact same date, and the receipt notes directly that no buffer separates them.
Does switching between business days and calendar days change which dates are solved?: Yes, a buffer of the same numeric size resolves to different actual dates depending on which mode is selected, since business-day mode skips weekends and any entered exclusions while calendar-day mode counts every day.