How AR invoice due data is calculated ?

Here is the payment term setting :

Billing cycle setting :

When I put AR invoice transaction date = 01/26/2025

my expect result is :

01/26/2025 + 30 days → next billing cycle = 02/25/2025 → next billing cycle (last day of month ) = 02/28/2025

but the fusion output result: 03/02/2025

When I put AR invoice transaction date = 11/26/2024

my expect result is :

11/26/2024 + 30 days → next billing cycle = 12/26/2024 → next billing cycle (last day of month ) = 12/31/2024

but the fusion output result: 12/30/24

When I put AR invoice transaction date = 12/15/2024

my expect result is :

12/13/2024 + 30 days → next billing cycle = 01/12/2025 → next billing cycle (last day of month ) = 01/15/2025

but the fusion output result: 1/14/25

May I ask how actually the billing cycle calculated ?

Is it related with any calendar setting which cause these unexpected result ?