Cbsubs: Allow access with partial offline payment

The title is explicit... My goal would be to allow to pay offline the amount of a special "2 years plan" in 3 time (for example 3 x $500 to pay monthly over 3 month) and to give immediate access at the first monthly payment.

I seen when customer confirm is order, we can Pay his pending basket by introducing the paid amount (received by bank transfer) which is supposed to be the same of price plan ($1500). However I tried to introduce $500 but this seem to not change nothing because is always $1500 which is recorded and invoiced.

Not possible to split the order in 3 basket of $500 and manually pay + generate corresponding invoice each month?

You'd need to set the price as $500 and the duration 1 month. They'd then need to renew monthly. There's no other way to split a larger payment into smaller payments.

Ok but as I said I need to set a 2 years plan. So after renewed 3 time and pay 3x500$ over 3 month, the plan will end...

??

You can't do that with CBSubs. As it's offline gateway I suppose you could ask them to pay it over the course of 3 months and enable them on first payment then just trust them to pay the other 2 times, but CBSubs does not handle such a scenario.