Most important is that as previously announced, Chase has adopted an Amex-style pop up jail for the SUB:

This credit card is unavailable to you if you currently have one open. The new cardmember bonus may not be available to you if you currently have any other personal Sapphire cards open, previously held this card or received a new cardmember bonus for this card. We may also consider the number of cards you have opened and closed, as well as other factors in determining your bonus eligibility.

We will have to wait until data points are available, but this potentially turns the previous once every 48 month SUB restriction into a once per lifetime restriction.