Hi,
Yes. HW5 was counted as two HWs, BUT if it was less than all the other HWs, then it was counted as one HW. For HW6, The story is almost the same, but with a minor difference. HW6 will be counted as two HWs in all cases. This means that HW6 will replace the minimum grade among the other HWs even if it is less than all of them. This means that it can be advantage or disadvantage. I hope it is clear now.
Regards,
Ahmad