Backwards compatibility/API stability

I'd like some help understanding your API backwards compatibility guarantees. If memory serves, you actually made some effort to not break client code in the past. For instance, earlier `/v1` endpoints were used and incompatible changes were exposed eventually through `/v2` ones.

And now I am seeing a change like [this one](https://github.com/alpacahq/user-docs/commit/b59f5ff087bc2336f55383f1f7db1319d6c7e0c9) merged, which randomly renames variants in the account activity for no apparent reason (`CSR` -> `CSW`), which, as per my understanding, is backwards compatibility breaking.

Can you please help me understand
1) what API stability guarantees you provide
2) how that change is in line with them

?