Based on what we've heard so far from Qualcomm, a 5G modem is supposedly going to be integrated into the Snapdragon 865, so everything you need to get connected to next-gen speeds will come built in.
While that's still going to happen as far as we know, a variation without the extra 5G could be used in markets where the cellular tech isn't available, to keep prices down.
With phones including the Samsung Galaxy S10 now available in 5G editions, consumers can now get their hands on 5G smartphones for the first time.
The infrastructure required to support 5G is still in the early stages of rolling out, however: in countries where it is available, you can only pick it up on certain networks in certain cities.
That situation will of course improve over time, but it sounds as though Qualcomm could decide to announce the Snapdragon 865 with and without an integrated 5G modem. We should find out later this year.
Having 5G integrated on at least one Snapdragon 865 model would give manufacturers extra room for other components, and maybe even a bigger battery.