​​​​​​​​​​​​​​​​​​​​​Good additional info Calchas, it does indeed look like a 3 day min stay from last stopover and indeed if you route through LAX it is almost impossible to not be at the three day mark when you hit NY.

But a couple other things I figured out in working with a TA on this:
(1) use a TA, its a commisionable fare so you shouldnt have to pay the TA (that’s really a cool feature for this cheap fare)
(2) when IB metal was running the ALG-MAD segment, it was impossible to find I space for a stopover in MAD. Air Nostrum appears to be letting out I space on the first/last segment in far greater amounts if you stopover in MAD.
(3) if you read the routing table carefully, you can fly ALG-MAD-LAX then LAX-JFK-LAX then LAX-LHR-MAD-ALG. In other words, a free premium cabin RT on thr 32T. The main limit on this is indeed a tough find of I space on the AA transcon. But if you are just 1 or 2 it should be fairly easy to pull off.
(4) the timing of the Air Nostrum flight allows you to do a tight same day connection to MAD-LAX, whereas when it was IB metal you had to stay overnight in MAD to take the MAD-LAX flight.