(This post is part of the Genuinely Approachable Sudoku (GAS) series.)
Everything here is close but not quite telling the truth (away by one). Maybe the solution can still be sorted out if you see the full picture and compare the local lies to find the global truths.

PDF

or solve online (using SudokuPad)

Theme: Stretching the Truth

Author/Opus: This is the 109th puzzle from Clover, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Standard Sudoku rules (Insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region). Also, every given clue is lying. The correct value is either one more or one less than the given clue.

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 6:00; One party hat (🥳): 11:00. All other solvers earn a 🦕: deceptive Diceratops.

Thomas Hits the GAS (highlight to view): 2:26, with SudokuPad replay file shared as a download for now (requires loading via settings menu with improvements expected before people should use this regularly).

Solution: PDF; solving video with explanation to be added later from GAS team.

Note: Follow this link for other less common variations of Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Daily GAS discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.