Domain Transfer of .cz TLD from GoDaddy to Route 53 Fails with Registry Error 2400

Based on the error message you're receiving, it appears there's a technical issue with the transfer process for your .cz domain. The error suggests there's a problem with the XML format being sent to the Czech registry (NIC.CZ), specifically related to the "period" element in the EPP (Extensible Provisioning Protocol) command.

While I don't have specific information about whether .cz TLDs are officially supported for inbound transfers to Route 53, the error you're encountering appears to be related to the communication protocol between AWS and the Czech registry rather than a general limitation.

This type of error typically requires intervention from AWS Support as it relates to the technical implementation of the transfer protocol. Since you've already contacted AWS Support, waiting for their response is the appropriate next step. They would have the necessary access to investigate and potentially fix the issue on their end.

In the meantime, you might want to ensure that all pre-transfer requirements have been properly met:

• Confirm the domain is fully unlocked at GoDaddy
• Verify the authorization code is correct and hasn't expired
• Check that the domain is eligible for transfer (not within 60 days of registration or previous transfer)
• Ensure any privacy protection services are disabled

If AWS Support doesn't respond in a timely manner, you might consider escalating your support case. While you could contact NIC.CZ directly, they would likely direct you back to your chosen registrar (in this case, AWS) as the registrar is responsible for implementing the correct protocol for communication with the registry.
Sources
Unable to Transfer Domain into Route 53 | AWS re:Post
Did Something During Domain Transfer | AWS re:Post
DomainTransferability - Amazon Route 53

The .cz domain is listed here: https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/cz.html under the "Geographic Top-Level Domains" section.