70k UR would transfer as 70k RR. It is not possible to book flights on Southwest using the Chase online travel portal. I am not sure if you can call to book a Southwest flight.
I always transfer my UR to RR if I need to book a flight because I like the flexibility (cancel any time and get my points refunded back) of booking directly with Southwest.
NFCU Flagship $32K | NFCU Cashrewards $42K | Discover IT $39K | SECU Visa $20K | Chase SW $24k | CSR $15K | Chase Bonvoy $11.5K | Chase Freedom $11.5K | Chase Amazon Visa 8.5K | AMEX Bonvoy $18.1K | AMEX Hilton Surpass $15K | AMEX Hilton Aspire $24.4K | AMEX Gold | Aviator Red $16K | Uber Visa 10k | Citi TY Premier $24.6K | BoA Premium Rewards 35k | BoA Cash Rewards Visa $31.5k | BoA Cash Rewards MC $23k | US Bank Cash+ $10k | USAA AMEX $6K | Cap1QS $11K | BJs MC $27.6K | Walmart MC $5.1K | Loft MC $25,000 | Macy’s Store/Amex $20K/$1K | BR Visa $10K | JCP $1K | VS $3.2K | Home Depot $5K | Lowes $8.5K | Target $14.5k
