Chase is okay with churning bank bonuses? When I opened my Sapphire checking account for the bonus, I intentionally kept it open for at least 12 months. Is that no longer required? In either case, I probably won't try to move $250K for the bonus this time, especially if I "should" keep it for an extended period of time. With Sapphire, at least You Invest balance counts to waive the monthly fee. I don't think it works with CPC. It has to be near zero interest checking/saving and/or fee-based investment accounts.
OP has no intention closing the account. And there is no evidence about churning. Beside - the offer only specifies that a new customer must keep the 250K for 90 days. So Chase can't really control what a customer would do afterward. 1-year is a good practice.
There are some noisy bankers who would do something above and beyond, like banning a customer. Of course, there are some nice bankers who would do something above and beyond as well, i.e. they know the trick and they work with you regardless. Unless you certainly know someone who will play ball, SM is a better way. In fact, the most of my bank accounts, Chase or otherwise, are closed by SM rather than in branch.
I would not recommend OP to move the money that quick after reviewing the offer. At the minimum, I would wait until the bonus has been deposited first.