Thank you TaxGuyBill

I do have a follow-up.  I went through Pub 936 (sorry, typo in my original post) again, and it seems that it may be aggressive to say that the refinance is still subject to pre-2017 limit of $1M.   I spoke with a colleague that takes a hardline view that any refinance now will be considered post-2017 and subject to the $750k limit, not the pre-refinance balance.

If you analogize Pre-2017 with the "grandfathered debt" shown in Pub 936 (which is pre-1987 debt), then I agree you may be able to continue deducting up to the $1M limit, but I'm not sure if the IRS would agree.

Curious yours and others thoughts.