system/I18n/Time.php
public function isBefore($testTime, string $timezone = null): bool
	{
		$testTime = $this->getUTCObject($testTime, $timezone)->getTimestamp();
		$ourTime  = $this->getTimestamp();

		return $ourTime < $testTime;
	}
public function isBefore($testTime, string $timezone = null): bool
	{
		$testTime = $this->getUTCObject($testTime, $timezone)->getTimestamp();
		$ourTime  = $this->getTimestamp();

		return $ourTime < $testTime;
	}
Determines if the current instance's time is before $testTime,
after converting to UTC.

@param $testTime
@param string|null $timezone

@return boolean
@throws \Exception