I logged this as a ticket to Splynx, and was asked by @alexcherry to post it to the forum so that others can benefit from the response.
We are using DHCP for client authentication, so we also use Simple Queue Trees via Splynx and the Mikrotik API which targets the customer static IPv4 address.
I have created a custom field for customer static IPv6 allocation in Splynx, however that network is not included in the Simple Queue Tree entries that are created via API.
Can you please advise how we can capture the IPv6 traffic for addresses allocated to customers within the same queues as the IPv4 traffic? We need to take into account that some customers may not have an IPv6 allocation yet, and we do not want things to break if the value is missing.