Verify before making a permanent change: wrong notch/tab layout on fitting.
High-risk starter answer - stop before cutting, drilling, coring, sleeving, enlarging, patching, or relocating any opening. Layout marks are not permission by themselves; match them to the latest drawing and field condition before cutting.
Ask when the cut affects structure, roof, rated wall, damper/access, grease/industrial duct, equipment, or another trade.
Watch out
Do not cut because the duct does not fit.
Check
Confirm the exact location from approved drawings and field marks.
Check what is above, below, behind, or inside the cut.
Verify whether the wall/deck/roof/shaft/beam is structural, rated, waterproofed, post-tensioned, or shared with other trades.
Check gridlines/control points, elevation, wall side, opening direction, and revision before cutting.
Steps
Confirm what you are cutting/drilling/fabricating.
Check latest drawing/shop detail.
Look for hidden utilities, structure, rated assemblies, roof membrane, or equipment parts.
Focus on the actual issue: wrong notch/tab layout on fitting.
Photograph or mark the condition if someone else needs to approve it.
Say this to your foreman
In Cutting, Holes, Penetrations & Field Fabrication, I'm looking at: Wrong notch/tab layout on fitting. What should I verify before I cut, drill, seal, cover, move, or install?