UTC Time

UTCTime         = year month day hour minute [ second ] [ u-time-zone ]
u-time-zone     = %x5A                           ; "Z"
/ u-differential
u-differential  = ( MINUS / PLUS ) hour minute
century = 2(%x30-39)                             ; "00" to "99"
year    = 2(%x30-39)                             ; "00" to "99"
month   = ( %x30 %x31-39 )                       ; "01" (January) to "09"
/ ( %x31 %x30-32 )                     ; "10" to "12"
day     = ( %x30 %x31-39 )                       ; "01" to "09"
/ ( %x31-32 %x30-39 )                  ; "10" to "29"
/ ( %x33 %x30-31 )                     ; "30" to "31"
hour    = ( %x30-31 %x30-39 ) / ( %x32 %x30-33 ) ; "00" to "23"
minute  = %x30-35 %x30-39                        ; "00" to "59"
second      = ( %x30-35 %x30-39 )                ; "00" to "59"
leap-second = ( %x36 %x30 )                      ; "60"
fraction        = ( DOT / COMMA ) 1*(%x30-39)
MINUS           = %x2D                           ; minus sign ("-")
PLUS            = %x2B                           ; plus sign ("+")
Where the ABNF allows invalid times, such as Feb. 31, 2017,
the values are considered invalid.
When the "Z" form of the time zone is used,
the time value represents universal coordinated time.
Otherwise, it represents a local time
in the time zone indicated by the `u-differential`.
The syntax corresponds to the `UTCTime` ASN.1 type.