Deadline extensions
Maintenance Planners use deadline extensions in situations where the aircraft cannot be brought to the repair station in time to do the maintenance. They approach the appropriate regulatory authorities and ask for permission to get a small extension; enough time to make it to a maintenance airport. They do this to avoid grounding the aircraft, which is what would happen if the deadline goes overdue.
This procedure is also useful before activating new revisions of requirements or maintenance programs, to avoid having many tasks become overdue because of the revision.
You extend the deadline by adding to the deviation on its scheduling parameter(s). When you extend a deadline by a number with fractions, for example, 2.5, and the deadline uses calendar days, weeks, or months as the scheduling parameter, the extension can cause the new deadline to be at a specific time during a day. To avoid a task from becoming overdue, Maintenix sets the deadline to 23:59 on the previous day. When you extend the deadline for a block, Maintenix also extends the deadlines for all sub-tasks (requirements) with the current driving deadline on or before the extended deadline for the block.
When you are looking at the due date of tasks from the Inventory Details page > Open Tasks tab > Due column, you can tell if the deadline has been extended when another date is displayed in parentheses after the due date. For example, if the Due column displays something like 19-SEP-2017 23:59 EST (26-SEP-2017 23:59 EST), the original due date is 19-SEP and the extended due date is 26-SEP.