Sort of related question. I've hit the spend requirement for the $500 Southwest credit. Next week when all the goodies become available, is this $500 credit likely to work the same way as with the OP's signup bonus? IOW, I book a Southwest ticket, and at the payment screen it gives me an option to apply the credit?

ETA: I think I found the answer to my question. I just need to use Chase Travel to book the Southwest flights, and charge to the Chase Sapphire Reserve. Statement credits up to $500, good through the end of 2026.

$75,000 Spend Benefit – $500 Southwest Airlines Chase Travel Credit for Chase Sapphire Reserve and J.P. Morgan Reserve Cards

After meeting the $75,000 spend requirements as described above, you, as the primary cardmember, will have statement credits automatically applied to your account for Southwest Airlines purchases made on Chase Travel, up to a maximum accumulation of $500 for the remainder of the calendar year in which you qualify expiring at the end of the following calendar year. The most you can have available at one time is $1,000 in statement credits if you qualify in consecutive years. The $500 Southwest Airlines Chase Travel Credit must be available at the time qualifying purchases are made to be applied to your account. See the Benefits section of your account on chase.com or the Chase Mobile® app for benefit status. Please allow 6 to 8 weeks for statement credit(s) to appear on your monthly credit card billing statement. We may reverse statement credits if an eligible purchase is returned, canceled, or modified or if you close your account within 90 days of receiving a statement credit. Any purchases that qualify for the $500 Southwest Airlines Chase Travel Credit will not earn points.