We'll likely replace my P85 with a 100D, for road trips. And the Model 3 would be for my wife's commuter - which we would likely not even purchase Supercharger support (if that's an option) - so if we take the road trip charging off the table, if the onboard software is better on the Bolt and it's available a year earlier than the Model 3, it will be pretty tempting to cancel our Model 3 reservation.
Tesla really needs to be proactive about this - and announce when they plan to provide screen mirroring or CarPlay/Android Auto. If they wait until after the Bolt goes on sale, they could start to see some defections - and once that starts, it may be harder to stop.