PAYE to IBR Transition Questions

I am on PAYE and need to transition to IBR because of the OBBBA. I have two questions about this:

1) IBR payment cap calculation

My interest capitalized at some point, so my current principal balance is higher than my original principal balance. When I leave PAYE and enroll in IBR, will my payment cap (the 10-year Standard Repayment amount) be based on the original principal of the loan, or on the current principal balance at the time I enter IBR?

2) Interest capitalization and PFH?

Once I'm on IBR, my monthly payments will be 15% of my discretionary income rather than 10%. I expect this will push my calculated payment higher than the standard payment cap, meaning I will no longer have a PFH.

I understand that losing your PFH status while on IBR triggers interest capitalization (unlike on PAYE). However, under current rules, a PFH is no longer required to initially enroll in IBR.

Suppose I intentionally lose my PFH status now (for example, by filing taxes jointly rather than separately with my spouse) and then leave PAYE to enroll in IBR. Will any of my current interest capitalize in this scenario? On one hand, I wouldn't technically be losing my PFH status while enrolled in IBR, but on the other hand, I would be entering the plan already lacking a PFH.