Recurring vs One-Time Affiliate Commissions

Hello,

I am about to add an affiliate program to help grow my SaaS project. I am deciding between adding a one-time vs recurring affiliate program.

I am considering giving a one-time 100% commission for the first month. My logic is that one-time commissions would be better for me since I will get most of the lifetime value of the buyer.

Alternatively, I could give a 30% recurring commission.
In this case, I would need the average customer to stay for at least 4 months for the 100% one -time commission to be the better one for me.

What are your thoughts?