REPLACE Function Returning Unexpected Results

tamerj1 so, becasue until someone else will say otherwise, you found a bug 🙂
In the mean time, I just jumped over it and solved it in another way (I'm adding the DAX Query):

EVALUATE 
VAR _CurrentTitle = SELECTCOLUMNS ( FILTER ('Table', 'Table'[Title] = "set field title case" ), "@Title", [Title] )
VAR _Length = LEN ( _CurrentTitle )
VAR T1 = GENERATESERIES ( 1, _Length, 1 )
VAR T2 = ADDCOLUMNS ( T1, "@Title", _CurrentTitle, "@SapceLocation", FIND ( " ", _CurrentTitle, [Value], BLANK ( ) ) )
VAR T3 = FILTER ( T2, [Value] = 1 || [@SapceLocation] = [Value] )
VAR T4 = ADDCOLUMNS ( T3, "@LetterLocation", IF ( [Value] = 1, 1, [Value] + 1 ) )
VAR T5 = ADDCOLUMNS ( T4, "@FirstLetter", MID  ( [@Title], [@LetterLocation], 1 ) )
VAR T6 = ADDCOLUMNS ( T5, "@CapitalLetter", UPPER ( [@FirstLetter] & "" ) )
VAR T7 = ADDCOLUMNS(
			T6, 
			"@Extracted Letter", 
			MID ( 
				[@Title], 
				[@LetterLocation],
				COALESCE(
					MINX( 
						FILTER(
							T6, 
							[@LetterLocation] > EARLIER([@LetterLocation])
						),
						VALUE([@LetterLocation])
					),
					_Length * 3
				) - [@LetterLocation] - 1
			)
		)


VAR T8 = ADDCOLUMNS ( T7, "@Extracted Letter Title Case", REPLACE ( [@Extracted Letter], 1, 1, [@CapitalLetter] ) )


VAR Result = 
    { 
        CONCATENATEX ( 
            T8,
            [@Extracted Letter Title Case],
            " ",
            [@LetterLocation],
            ASC
        )
    }
RETURN
    Result

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