Gotcha, thanks for explaining. One thing to note is that if you make a copy of a doc, IDs of object within the doc will remain the same. So you could potentially just hard-code the table ID there and it should work in copies of your doc.
We only recently launched v1 of our API this summer (Coda API v1 Launched) and don’t have any plans to work on a newer API. We could support updating columns in the current API without breaking changes, but there has been little demand for it so we’ve been prioritizing other non-API work.