Change invoice number

Hello friends,
I’d like to use JetpackCRM, I even did some translating last night (Spanish), I really enjoy testing your product.
Invoices is one of the features I’ll use and I’m not able to find: where can I change the invoice number? this is in order to have JetpackCRM start the invoices were the old invoicing system left off.
Thanks for your help.
Renato