In the maintenance plan, activity definitions that are based on contract activity definitions are not easily recognizable as such. This may cause problems when the maintenance planner edits an activity definition's period and subsequently generates orders in Planned Maintenance .

For example: the maintenance planner can manually adjust the start-/ end date of the activity definition to an extent that the linked contractual period (as defined in the contract line) is no longer covered. This would result in orders without a contractual basis. Therefore, maintenance planners can be warned or stopped by the system when making changes to this type of activity definition. Planon administrators can make a setting to either show a warning or actually prevent users to plan outside the contractual period, with the Prevent activity definition period from falling outside contract line period? setting in Field definer .