Add Firebase dynamic link TXT in route 53

Hi,

From the description of your issue it appears you are running a GetChange API call following the creation of the TXT records for Firebase. From the documentation here[1] I can confirm that the INSYNC status indicates that your channges have propagated to all Route 53 DNS servers managing the hosted zone.

Reference: [1]. AWS Route 53 GetChange documentation https://docs.aws.amazon.com/Route53/latest/APIReference/API_GetChange.html

Thank you.