You are using terms that describe very different things.
Six months ago, the term hassio was replaced by Home Assistant OS. If this is what you are currently using then you have the Supervisor and the ability to use Add-Ons. Home Assistant OS consists of an operating system and several docker containers, one of which contains the python code that forms Home Assistant. To upgrade it, select Supervisor > Dashboard > Update.
Home Assistant Core is different. It is just the python code. It is not in a docker container and cannot be used to upgrade Home Assistant OS.
The four official installation methods are described here.
Would it be fair to say that you have Home Assistant OS 0.115.0 and you wish to upgrade to the latest version of Home Assistant OS 0.118.4? If so, then the procedure is as I described above: Supervisor > Dashboard > Update. Let us know if that’s what you did (and that’s what produced the warning messages you posted) or if you did something different.