Issue:
This is the projected 2020 apportionment changes. These projections show a confidence level beyond the margin of error too with regards to the difference in priority value between seat 435 and seat 436. Your projections seem to not line up with this.
2020 is still years away...different growth rates result in different apportionments
The projections I found show a difference in priority values for seat 435 and 436 beyond the margin of error with just 2.75 years out. There is no way your projections should be any different unless you are using incorrect data.
there are multiple projections showing a battle between MT-02 vs. TX-39 depending on future growth
According to my calculations, AZ-10 is seat 435, and MT-02 is seat 436, with the difference between the 2 priority values beyond the margin of error.