Gifting a phone to a family Member and how it works with Apple Care +

I bought my first iphone last year, a 12 max pro. Love it. I had not planned on upgrading quite yet to the 13, but my husband wants an iphone and told me to get the new 13 and to gift him my 12 pro max instead of trading it in. So, I preordered this morning with apple care + loss and theft protection. I have a similar plan on my old 12 pro max. When I transfer the phone to my husband, will he still be covered by the apple care +? I want to be sure the 12 pro max is still covered. I assumed the plan is tied to the phone, not the phone number. Was that a bad assumption?