Help plotting my next moves... CSP+Autograph?

So, I've got two cards in mind; one to churn, one to keep:

1. Sapphire Preferred
2. Autograph

I'm happy with my current stack, but I like the Autograph having category coverage on gas and broad travel with no AF. That's probably a keeper for me. However, the SUB is kinda puny, and I have car maintenance in May for about $1,000 and about $1,000 in travel expenses reimbursed through work that'll be coming up in early June, so I really want to get some value out of those charges.

That's where I'm thinking I open the CSP, churn the SUB, then downgrade in a year to a Freedom. I can get plenty of use out of Southwest and Hyatt. That would put me at 5/24 for the next year, though, which is why I thought I'd pick the brain trust here for opinions.

• Current cards: (list cards, limits, opening date)
  • US Bank Cash+ ($12,500, December 2017)
  • C1 Savor ($6,000, June 2025)
  • WF Active Cash ($5,500, June 2025)
  • C1 Venture X ($30,000, October 2025)
• FICO Score: 766
• Oldest account age: 9 years, 9 months
• Chase 5/24 status: 3/24
• Income: $50,000
• Average monthly spend and categories:
  • dining $800 (for two people)
  • groceries: $400 (for two people)
  • gas: $100
  • travel: $200 (averaging 4-5 trips a year, mostly domestic)
  • other: $100
• Open to Business Cards: Not really looking there at the moment
• What's the purpose of your next card? Category coverage and SUBs
• Do you have any cards you've been looking at? See above

Also, if I go this route I'm thinking I'd try to just open them both on the same day. I know I'm pre-approved for both. Seem like the right idea?