Boundary Mode: Flexible vs Fixed

When you drag a stage or segment boundary, boundary mode controls what happens to the segment next to it.

Want to shift proportions without changing the total stage length? Use flexible mode. Want to extend a segment and push the impact forward? Use fixed mode.

Boundary mode and sync/independent mode are two separate settings — you can combine them however you like.


Flexible Mode

When you drag a boundary, the adjacent segment shrinks proportionally to accommodate, and the stage’s total length stays the same.

When to use it

  • You want to rebalance proportions within a stage without affecting its total length
  • You need to adjust the split between main work and revision buffer without touching later stages

How to switch

  • Click the boundary mode toggle in the timeline toolbar and select “Flexible”
  • Flexible mode is the default

Behavior

  • Drag the right boundary of the main work segment right → main work gets longer, the adjacent revision buffer shrinks proportionally
  • Total stage length stays the same; only the internal proportions change

Fixed Mode

When you drag a boundary, the adjacent segment doesn’t shrink — it gets pushed, so the stage’s total length changes.

When to use it

  • A segment’s day count is a hard minimum — it can’t be compressed
  • You want to extend a segment and let the impact ripple forward rather than squeezing what’s next to it

How to switch

  • Click the boundary mode toggle in the timeline toolbar and select “Fixed”

Behavior

  • Drag the right boundary of the main work segment right → main work gets longer, the adjacent revision buffer’s start date moves back, and the total stage length increases
  • Fixed mode + sync mode: extending a stage also shifts later stages
  • Fixed mode + independent mode: extending a stage doesn’t move later stages (may create overlap)

Flexible vs Fixed: quick comparison

ActionFlexible modeFixed mode
Drag boundaryAdjacent segment shrinks; total length unchangedAdjacent segment shifts; total length changes
Effect on later stagesNone (total length unchanged)Yes, if sync mode is on
Best forAdjusting proportionsProtecting a segment’s minimum length