When AMD officially announced their Threadripper 3 processors there were two initially with a tease of a flagship part, which was the 3990X (64-core/128-threads). The 3960X is a 24-core, 48-thread part, while the 3970X is 32-core, 64-thread. So you can see there is quite a big gap between the 3970X and the 3990X, not only in core-count, but naming as well. It appears we will see a 48-core 3980X which would sit between the 3970X and 3990X.
Much like the 3990X we can expect the 3980X to be built with eight “Zen 2” chiplets (CCD). Each CCD will be configured with 6 cores (3 per CCX), making up 48 cores on the package. We can also expect the clock speeds to remain under wrap until close to launch date as they have done with the 3990X. AMD is expected to launch both the 3980X and 3990X sometime in 2020. If AMD plans to target the sub-$3000 range they could make Intel’s W-3175X obsolete in both performance and value.