I think that really depends on the implementation details. For example, consider a thought experiment where artificial neurons can be created that behave just the same as biological ones. Then each of your neurons is replaced by an artificial version while you are still conscious. You wouldn't notice losing a single neuron at a time, in fact this regularly happens already. Yet, over time, all your biological neurons could be replaced by artificial ones at which point your consciousness will have migrated to a new substrate.

Alternatively, what if one of your hemispheres was replaced by an artificial one. What if an artificial hemisphere was added into the mix in addition to the two you have. What if a dozen artificial hemispheres were added, or a thousand, would the two original biological ones still be the most relevant parts of you?