// Calculate the delay until the next trial
$delay = (($retrial + 3) ** 4) + (rand(1, 30) * ($retrial + 1));
- $next = DateTimeFormat::utc(date('c', time() + $delay));
+ $next = DateTimeFormat::utc('now + ' . $delay . ' seconds');
dba::update('queue', ['last' => DateTimeFormat::utcNow(), 'retrial' => $retrial + 1, 'next' => $next], ['id' => $id]);
}