If they're going to include the month and year as part of the version number, they should at least use big endian dates like gemini-2.5-flash-preview-2025-09 instead of 09-2025.
Or, you know, just Gemini 2.6 Flash. I don't recall the 2.5 version having a date associated with it when it came out, though maybe they are using dates now. In marketing, at least, it's always known as Gemini 2.5 Flash/Pro.
It always had dates... They release multiple versions and update regularly. Not sure if this is the first 2.5 Flash update, but pretty sure Pro had a few updates as well...
This is also the case with OpenAI and their models. Pretty standard I guess.
They don't change the versioning, because I guess they don't consider it to be "a new model trained from scratch".
If only there was some of versioning nomenclature they could use. Maybe even one that is … semantic? Oh how I wish someone would introduce something like this to the software engineering field. /s
In all seriousness though, their version system is awful.