I've been trying to set start times for different flights of competitors. The addMinutes function seems to update every variable associated with the "ONE" I'm trying to alter. Is this the expected result, or am I missing something really simple?
Thanks for your assistance,

public function test_i18_addminutes( $a_time = null )
{
    $b_time = $a_time ?: Time::now();

    for ( $i = 1; $i < 5; $i++ ) {
        $use_time = $b_time;
        debug( "BTIME: $b_time   USETIME: $use_time" );

        for ( $j = 1; $j < 7; $j++ ) {
            $mytime = $use_time->addMinutes( 15.0 );
            debug( "     MYTIME: $mytime      BTIME: $b_time   USETIME: $use_time" );
        }
    }
    $this->redirect( '/' );
}

\src\Controller\TestsController.php (line 89)
'BTIME: 9/14/21, 6:09 PM USETIME: 9/14/21, 6:09 PM'
' MYTIME: 9/14/21, 6:24 PM BTIME: 9/14/21, 6:24 PM USETIME: 9/14/21, 6:24 PM'
' MYTIME: 9/14/21, 6:39 PM BTIME: 9/14/21, 6:39 PM USETIME: 9/14/21, 6:39 PM'
' MYTIME: 9/14/21, 6:54 PM BTIME: 9/14/21, 6:54 PM USETIME: 9/14/21, 6:54 PM'
' MYTIME: 9/14/21, 7:09 PM BTIME: 9/14/21, 7:09 PM USETIME: 9/14/21, 7:09 PM'
' MYTIME: 9/14/21, 7:24 PM BTIME: 9/14/21, 7:24 PM USETIME: 9/14/21, 7:24 PM'
' MYTIME: 9/14/21, 7:39 PM BTIME: 9/14/21, 7:39 PM USETIME: 9/14/21, 7:39 PM'
'BTIME: 9/14/21, 7:39 PM USETIME: 9/14/21, 7:39 PM'
' MYTIME: 9/14/21, 7:54 PM BTIME: 9/14/21, 7:54 PM USETIME: 9/14/21, 7:54 PM'
' MYTIME: 9/14/21, 8:09 PM BTIME: 9/14/21, 8:09 PM USETIME: 9/14/21, 8:09 PM'