My calculations suggest Trump will get about 1243 delegates.
The only states I see Trump as potentially NOT winning are Wisconsin, Pennsylvania, Nebraska, Montana, New Mexico and South Dakota.
IIRC, Trump is currently up by ~16% or so in PA.
I got Trump around 1,408 delegates even with Trump losing all delegates from ND, SD, CO, and losing all 54 unbound delegates from PA despite winning the state in my scenario. I give NE (36 delegates) to Trump a WTA closed primary state because of his superior campaigning and the NE primary is over a month away. He will have even bigger momentum then and Cruz will be mathematically eliminated for getting the required 1,237. Trump taking 1,237 is about slam dunk.
I’d like to see your breakdown of delegates.
Trump will win PA, but the delegates won’t vote for him (most likely). If he does win PA and he’s close to 1237 then he may squeak across as some unbound delegates vote for him in the first round to put this to bed and avoid a fight. Other than that there’s no way he’s the nominee without 1237.
California is proportional and closed (I think) so that should be interesting. I think Kasich and Cruz will do better than you think in Cali. May not win it but will get lots of delegates. But then I’m not 100% sure how CA spreads the delegates around.
Can you break out your delegates by state so I can consider your 1243 projection in context. When I did the math I had Trump needing nearly all WI delegates to hit 1237.