Staying true to the short stories/ novels isn't necessary (it already diverts). This question is about whether Apple+ will retain and produce the show until it ends, more or less around the same era and plot points of the novels. For context, the novel series spanned 5 books, not including the prequels, which aren't necessary to resolve this YES. From what little I can tell, the first two seasons are partially mixing the first and second books with some new material, and they'll have a challenge dealing with a rotating cast eventually.
If Apple+ drops the show, even if it's later picked up by someone else, this resolves NO. If they pick the show back up before someone else does, I'll endeavor to unresolve it. If the show "ends" in a way clearly discordant with the series, it also resolves NO.
Otherwise this resolves YES at the closure of the series.
The close date of this question is speculative and subject to change as necessary.