It looks like you have:
two at: 44" x 74"
two at: 32" x 74"
Looks like you'd be pretty close on your plan from this chart by Sleepys - full is 54x75 and twin is 39x75. In both cases, you're going to have some extra (which is fine- order 2"-4" foam pads from The Foam Factory and the folks sleeping on those beds will love you forever.
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Officially a SOB with a 2022 Jayco Precept 36C
Checkout my site for RVing tips, tricks, and info | Was a Fulltime Family for 5 years, now we're part-timing on long trips
Assuming one can trust the advertised measurements. It looks like the measurements are 72" x 80" on the king which puts it splitting the king (76" x 80") vs. california king (72" x 84") in sizes.
__________________
Officially a SOB with a 2022 Jayco Precept 36C
Checkout my site for RVing tips, tricks, and info | Was a Fulltime Family for 5 years, now we're part-timing on long trips