Description:
------------
At http://php.net/manual/en/datetime.createfromformat.php, description of format character “!” And “|” are as follows:

“!”
Resets all fields (year, month, day, hour, minute, second, fraction and timezone information) to the Unix Epoch

“|”
Resets all fields (year, month, day, hour, minute, second, fraction and timezone information) to the Unix Epoch if they have not been parsed yet

And in the rest of this document, the UNIX epoch is explained as follows:

> The Unix epoch is 1970-01-01 00:00:00 UTC.

But actually, they appear to reset to 1970-01-01 00:00:00 in the resulting timezone, not UTC.

% php -d date.timezone=Asia/Tokyo -r 'var_dump(DateTime::createFromFormat("!", ""));'
object(DateTime)#1 (3) {
  ["date"]=>
  string(26) "1970-01-01 00:00:00.000000"
  ["timezone_type"]=>
  int(3)
  ["timezone"]=>
  string(10) "Asia/Tokyo"
}
% php -d date.timezone=Asia/Tokyo -r 'var_dump(DateTime::createFromFormat("!", "")->getTimestamp());'
int(-32400)
% php -r 'var_dump(DateTime::createFromFormat("!", "", new DateTimeZone("Asia/Tokyo")));'
object(DateTime)#2 (3) {
  ["date"]=>
  string(26) "1970-01-01 00:00:00.000000"
  ["timezone_type"]=>
  int(3)
  ["timezone"]=>
  string(10) "Asia/Tokyo"
}

Since the current behavior is more useful, I think this is a problem of documentation.