Hi,
I was able to reproduce the problem on my end and fixed it.
It was caused by another patch which added extra checks on the addresses during the checkout to properly refresh elements when addresses would be added/removed. This change had an effect on that special case as the check for that special case didn't take into account the extra checks of the other patch.
The fix is quite simple. Change the line:
if(!in_array($markerName, array('billing_address', 'shipping_address','user')))
to:
if(!in_array($markerName, array('billing_address', 'billing_addresses', 'shipping_address', 'shipping_addresses','user')))
in the file administrator/components/com_hikashop/helpers/checkout/login.php and that's it.
We'll add that fix on our end too.