Hello @Mal6,
All payment issues should be discussed by the guest with Airbnb. Hosts can't help directly.
If it's a 6 week stay then that automatically qualifies as a long term stay as it's more than 28 days.
The guest will be charged upfron for the first month. They will be charged the remainder a month later.
When am I charged for a reservation?
There is a "Pay less upfront" option that Airbnb may offer guests when they are about to pay for a reservation. If it's not offered to the guest on the payment page then the option is not available to them.
I don't know if the option is available for long term stays.
Can I split the cost of my reservation across multiple payments?
pay-less-upfront-terms
Steve.