How do I get round the issue of abandoned cart email not triggering before payment button is pressed in BigCommerce?

I have found out that the abandoned cart email is not triggered until the payment button is pressed in the one-step checkout in BigCommerce, so if a customer enters checkout and fill in addresses etc and then abandon cart, the email is not triggered. Only time to trigger is when the button at the payment section is pressed. This is a major weakness. I don't know if Omnisend has any plan to improve this with BC, or do I have to live with this "abandoned payment" rather than "abandoned cart" function.