It depends on when and if you want to get another card of the same type.

Many datapoints suggest most people need to cancel one personal card to be able to get another one. I'm not sure of the timing, but I am sure of the order of events. (I haven't done the personal card myself in a while, because I'm trying to stay under 5/24. Personal AS cards count against Chase 5/24, business AS card don't.)

There's not enough datapoints on biz cards to know how likely this is to be necessary. In my case, I just assumed it is, and cancelled a month or so after the miles hit my AS account. Then waited a few months (I was busy with other offers) and opened another one.

There are also theories that how risky this is depends on the BofA side on how far you push it (trying to be "fast" with 2 cards may be riskier than trying to be "fast" with just 1 card, I dunno), and then that on the Alaska Airlines side it's better to have a mix of miles earned in different ways, not just BofA card postings ad infinitum: take an Alaska paid flight now and then, and/or use Alaska Airlines Dining now and then, and/or use Alaska Airlines Shopping now and then, anything so it doesn't look to Alaska like the only way you're earning AS miles is by endlessly churning the BofA cards.