Activity Changes Deep Dive
Applies to: All tiers Last updated: 27-Feb-2026
Overview
The Activity Changes view provides a detailed breakdown of every modification between your current and baseline schedules. Changes are categorised into three severity tiers — Hard, Medium, and Soft — with 20 distinct change types. Click any change type to drill into individual affected activities.
Prerequisites
- Two schedules loaded for the same project — one marked as Current, one as Baseline
- The Comparison tab open and comparison complete
Three-Tier Change Model
Hard Changes (Red)
Direct, deliberate user modifications that fundamentally alter the schedule plan.
| Change Type | Icon | What It Detects |
|---|---|---|
| Original Duration | Clock | Duration baseline changed |
| WBS Assignment | Tree | Activity moved to a different WBS node |
| ID / Description | Edit | Activity ID or name changed |
| Relationships & Lag | Link | Relationships or lag values added, deleted, or modified |
| Constraints | Lock | Constraints added, deleted, or changed |
| Resource Assignment | User | Resources assigned, removed, or modified |
| Activity Settings | Settings | Schedule options changed at activity level |
| Activity Codes | Tags | Activity code assignments changed |
| UDF Changes | File | User Defined Field values changed |
| New Activities | Plus | Activities present in current but not in baseline |
| Deleted Activities | Delete | Activities present in baseline but not in current |
| Calendar Definition | Settings | Calendar work patterns changed |
| Calendar Assignment | Calendar | Activity assigned to a different calendar |
Medium Changes (Orange)
User updates to actual progress data.
| Change Type | Icon | What It Detects |
|---|---|---|
| Actual Start Date | Calendar | Activity started, or actual start date moved (including backdated) |
| Actual Finish Date | Calendar | Activity finished, or actual finish date moved (including backdated) |
| Remaining Duration | Clock | Remaining duration modified |
| Progress % | Clock | Physical or duration percent complete changed (or reduced) |
Soft Changes (Blue)
Calculated values that changed as a consequence of Hard and Medium changes.
| Change Type | Icon | What It Detects |
|---|---|---|
| Start / Finish Dates | Calendar | Early or late start/finish dates shifted |
| Calculated Duration | Clock | At-completion duration changed |
| Total Float | Clock | Total float value changed |
| Free Float | Clock | Free float value changed |
| Critical Path Status | Clock | Activity moved on or off the critical path |
Accordion View
Each severity tier renders as a collapsible accordion section. Within each tier:
- Change type rows — display the type label, icon, count badge, and description
- Click a row → opens the Change Drawer (80vw wide) filtered to that specific change type
The accordion highlights non-zero change types and dims/hides types with zero matches.
Card View
An alternative presentation showing changes as glassmorphic cards grouped by severity:
| Card Element | Description |
|---|---|
| Icon | Semantic icon matching the change type |
| Count badge | Number of affected activities |
| Label | Change type name |
| Category glow | Card border colour matches severity (red/orange/blue) |
Cards with zero changes show an empty state. Clicking a card opens the same Change Drawer.
Activity Filters
Filter the changes view to focus on specific areas:
| Filter | Description |
|---|---|
| Impact Level | Filter by Hard, Medium, or Soft |
| Change Category | Filter by specific change type |
| Change Severity | Filter by Critical, Major, Minor, etc. |
| WBS | Filter to a specific WBS branch |
| Activity Codes | Filter by activity code values |
| Text Search | Search by Activity ID or Name (300ms debounce) |
Change Drawer
When you click a change type, a full-width drawer slides in from the right showing all affected activities:
- Activity grid — sortable columns showing the Activity ID, Name, WBS, and the changed field values (before → after)
- Field-level diff — highlights exactly which fields changed, with old and new values side-by-side
- Severity badges — each activity shows its assigned severity level
Integration with Other Comparison Views
The Activity Changes view works alongside the other five comparison tabs:
| Tab | Focus |
|---|---|
| Activities | Activity-level changes (this page) |
| WBS | Changes aggregated by WBS hierarchy |
| Resources | Resource loading comparison charts |
| Activity Codes | Activity code value changes |
| UDFs | User Defined Field changes |
| Relationships | Relationship changes |
See the Comparison Overview for details on all six tabs.
Tips & Best Practices
- Focus on Hard Changes first — they indicate deliberate plan modifications that drive schedule variance
- Soft Changes are expected after Hard and Medium changes; they show the ripple effect of modifications
- Use the WBS filter to focus on a specific work area during schedule reviews
- Export the change drawer data for inclusion in monthly progress reports
- Compare the number of New Activities vs Deleted Activities to understand scope growth or reduction
Related Documentation
- Comparison Overview — Full comparison feature guide
- Selecting Schedules — How to choose current vs baseline
- Quality Overview — Automated schedule quality analysis