@hasenradball I checked with @d-a-v, and it looks like I'm wrong in this case. Or rather, it's not quite that simple. The sntp api provided by Espressif in their sdk, which is documented in their 2c reference doc, is not really theirs, but it's a part of lwip. I thought the sdk had a layer over lwip, but that's not the case. In our core, we moved away from Espressif's way of using lwip by migrating from their lwip1.4 branch to our own branch of lwip2. Therefore, it's possible the issue is in our lwip glue code, and that's on us.