The reasons why your score on one model is higher or lower than on another will be specific to your profile. EX2, EX8, and EX auto scores are different algorithms, so they will each assess what is in your profile somewhat differently. Auto scores, in addition to having a different score range, also weigh the presence or abscence of auto loans, but mortgage and score 8 don't see them differently from any other installment. Mortgage scores, to my knowledge, don't weigh a mortgage differently from general installments, but they will still look at what is in your profile a little differently, though they won't necessarily come out lower than score 8. For example, FICO8 has an anti-abuse algorithm for AU accounts, as well as an apparent penalty for all AU accounts reporting $0 balances, both of which the older mortgage scores lack. If a profile would get significant aging and util boosts from AU accounts, it may look better to the mortgage algos than it does to FICO8. If you want to know more about why they might be different in your specific case, you could post your profile details and the community might have some insight.
To cancel your Experian trial and not be charged, you just need to switch your account to the free version, which you can do now. The account status won't actually change until the trial expires.
