Happened to P3 acct - lost 65k (5k spend +60k bonus for P Plat) in 2019 due to RAT team. reopened a Schwab card in 2021 - no problem getting bonuses so far
I was careless and trying to save the Amex - as I had a Business Plus card, I thought it will keep Amex MR alive.
Now, if you plan to do things like that empty Amex MR first then it does not matter.
2020 March when pandemic started I cashed a whole lot of Amex in multiplayer accounts P1-5 before closing them all after getting rebates in Feb
However cutting it fine by closing the account just a couple days after rebates may matter - may not if you do not intend to keep MR around

Last year got a whole lot of offers in early Jan - GoldBelly - Home Chef, Home Depot etc etc on my account - did them all and then downgraded card to Green card at annual fee time

Just now, while going to verify this from the Amex account, I saw a 140k offer to upgrade to my other charge card - Business Gold - to business Plat card for 10k spend
The I got an offer to add employee cards offer for 20k bonus for 4k spend x5 = 100k bonus
Plan 4k x 5 on 5 employee cards - will qualify for both offers = 140+100= 240 bonus for 20k spend = tax time coming up = 10% rebate at least

Make Purchases More Rewarding with Valuable Business Platinum Benefits You've been selected to upgrade to the Business Platinum Card®, a Card with new premier benefits and exclusive offers designed for you, your business, and the road ahead. As a welcome offer, earn an extra 140,000 Membership Rewards® points† after you spend $10,000 in purchases on the Card in the first three months of Card Membership. Points have no expiration date, so you can use them when you're ready.† ‡†Offer & Benefit Terms

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