CBSubs Options

I was wondering whether it would change something for our use of CB Triggers onCPayAfterPaymentStatusUpdateEvent as we use mc_gross, payment_gross, payment_type, payment_method and payment_status to transfer data to our invoicing component ?
Are periodic payments dealt with like recurring ones ?

No payment behavior changes. Everything still behaves as it does now except users can impact the price based off options selected or price/duration selected.

Can we have for instance 12 periodic payments for an annual plan with a recurring one year subscription for this plan ?

No, this lets you override the price via pricing options or lets you have multiple price/duration combinations per plan so users can select the duration. This helps avoid needing 3 plans for example if you want 3 different durations for your plan. It does not create a 1 year commitment then bill them monthly, which isn't necessary as you can just create a monthly plan.