I understand your concern about the potential impact on your organization's testing and deployment efforts. It's important to consider the specific needs and priorities of your organization when making decisions about software updates.
While MS 14.33 may be rock solid for you at the moment, it's worth noting that newer releases include important security patches and bug fixes. Waiting until MS 16 becomes GA might mean missing out on these critical updates for a longer period of time.
One approach you could consider is to evaluate the potential impact of upgrading to MS 15.22 by initiating testing of this version to simulate your organization's specific use cases and scenarios. This will help you determine whether the benefits of the new release outweigh the potential challenges of retesting and redeploying. While this may initially seem like a duplication of effort vs waiting for MS 16, it's important to recognize that testing MS 16 will build upon the foundation laid during the testing of MS 15. By thoroughly testing MS 15, you gain valuable insights into the potential impact of future updates, such as MS 16. This allows you to proactively address any issues, reducing the overall effort required when transitioning to MS 16.
Ultimately, the decision to upgrade depends on the specific needs and risk tolerance of your organization. Taking a cautious and well-planned approach to testing and deployment can help minimize disruption and ensure a successful transition to a newer release.