Yesterday we released the HTTP API v2.
In this new version, we have renamed all the endpoints so that they are consistent with the new Kit nomenclature we started using on the SDK 2.0.0. The idea is that if you are working with payments, you should be able to quickly find the relevant methods under PaymentsKit both in the SDK and the HTTP API.
Besides that, there is no actual change in functionality. So upgrading should be as easy as updating the URLs.
However, if it is not convenient for you to update right now, you can still use the older HTTP API v1 since we are not planning on shutting it down yet.