Stub zone automatic update of NS records

[#1]

I would like to ask if a stub zone will regularly update the list of NS records that are stored in the corresponding Master server/s.

I have done some tests and I could see that right after restarting the DNS service a TCP DNS query is performed where all NS records are requested and then locally stored when the response from the  Master Server (external to the grid) is received. This can be checked by issuing a "dig <stub domain name> +norecurse soa" command locally on the device where the zone is defined.

However no additional TCP DNS queries like that first one is seen afterwards (i have left a network capture for 2-3 hours). Isn't one of the advantages of stub zones the fact that you can change the list of NS servers on the Master Server without having to change or touch anything on the stub zone? The behaviour that I have seen does not go in that direction, since a DNS restart would be required.

Thanks in advance.

[#2]

Hello, I would like to ask if anybodoy has an answer to this question. Thanks in advance!!!