SELECT
devicename,
(
CASE
    WHEN
        LEN(SUBSTRING(devicename,CHARINDEX('-',devicename)+1,LEN(devicename))) = 2
    THEN
        '00' + SUBSTRING(devicename,CHARINDEX('-',devicename)+1,LEN(devicename))
        + '-'
        + SUBSTRING(devicename,0,CHARINDEX('-',devicename))

    WHEN
        LEN(SUBSTRING(devicename,CHARINDEX('-',devicename)+1,LEN(devicename))) = 3
    THEN
        '0' + SUBSTRING(devicename,CHARINDEX('-',devicename)+1,LEN(devicename))
        + '-'
        + SUBSTRING(devicename,0,CHARINDEX('-',devicename))

    ELSE
        SUBSTRING(devicename,CHARINDEX('-',devicename)+1,LEN(devicename))
        + '-'
        + SUBSTRING(devicename,0,CHARINDEX('-',devicename))
END) AS reversed

FROM WPW_GPS.dbo.View_TimeUnitInService