My head is spinning trying to get APR, HPML and HOEPA rules straight.

Does the definition of finance charges/prepaid finance charges and the comparison standard (avg prime offer rate vs comparable Treasury security) for HOEPA and HPML become the same on 10/1? I could swear I read this somewhere but http://www.bankersonline.com/regs/226/226-32.html show any amendment.

This article from the Summer 2009 issue of FDIC's Supervisory Insights does a nice job of comparing the HMPL provisions of Reg. Z to the HOEPA provisions.

There are also changes to Reg. C (HMDA) that apply to HMDA-covered applications received on or after 10/1/09. Take a look at the instructions in Appendix A to Reg. C regarding the rate spread calculation. http://www.bankersonline.com/regs/203/a203-a.html

HOEPA will still be based on APR and Charges and fees exceeding 8%/10% and the APR will still be compared to the comparable Treasury Constant Maturity.

HPML is based only on the APR exceeding 1.5%/3% and it will be compared to the AOPR.

Is it possible to have a HPML that is not a HOEPA loan and visa versa?

Yes. You could have a HOEPA loan because of fees (credit insurance, for example), but the APR is < the HPML threshold. Likewise, you could easily have a HPML where the APR is not at the HOEPA threshold.