2 months deferred prevents problems
There's a reason a lot of employers make 2 months deferred finance a mandatory requirement in their BYO/self-managed Lease framework.
Anything less and the finance payments start falling into arrears. Finance takes priority, so your running expense budget gets raided to play catch-up, and now you're short on fuel, servicing and rego as well.
Here's the part that catches people out. If the salary packaging provider sets up your payroll deductions later than they needed to, and your first (sometimes second) finance payment doesn't get made on time, the financier chases you for it. Not them. You. And there is effectively no recourse, because the entity that caused the problem isn't the entity you now owe money to.
My bias: I work in this space. A chunk of what I do is advocating for people stuck with self-managed Leases who set the finance up through an introducer, who then stopped answering calls and emails once the sale was done. It happens constantly. It's preventable, but not everyone heeds the warnings.
For what it's worth, I stay with clients from the day I quote through to the day they pay their residual. Fully maintained, self-managed, BYO, doesn't matter. I'd rather be the person they can call in year three than win a race to the bottom on rates.