Must-coexist

Some pairs cannot be staggered. Flag the two items that have to be true at the same moment, not merely both done eventually, because finishing one early and letting it lapse leaves you no further ahead.

Some pairs cannot be staggered. Flag the two items that have to be true at the same moment, not merely both done eventually, because finishing one early and letting it lapse leaves you no further ahead.

Example

On the 40-item launch list, the staging environment and the QA contractor must overlap. Book her for three weeks in April but keep staging live only through March, and both boxes get checked while zero testing happens.