Provide column header from selection

BrianJm86 One possible dynamic array formula for MS365 would be:

=LET(
    table, Master!A1:BE10,
    data, DROP(table, 1, 4),
    rowId, SEQUENCE(ROWS(data)),
    recordCount, BYROW(data, LAMBDA(r, COUNTIF(r, "x"))),
    maxCount, MAX(recordCount),
    newRows, maxCount-recordCount,
    cols, SEQUENCE(, maxCount),
    unpivot, HSTACK(TOCOL(IFS(recordCount>=cols, rowId), 2), TOCOL(IFS(data="x", DROP(TAKE(table, 1),, 4)), 2)),
    results, WRAPROWS(DROP(SORT(VSTACK(unpivot, EXPAND(TOCOL(IFS(newRows>=cols, rowId), 2),, 2, ""))),, 1), maxCount),
    HSTACK(TAKE(table,, 4), VSTACK("Week "&cols, results))
)

It may seem like a lot but is relatively efficient and should perform quite well with 1,000+ rows of data. Adjust the range reference accordingly to select your entire table range (including the header row).

Results

Please see the attached workbook...