We have 3 separate Modernbill 4.x systems that we wish to merge into 1 single WHMCS system.
Using the provided migration scripts, the issue we face is that there could be duplicated invoices numbers etc. This cause a clash and can result in clients ending up with invoices from our different systems.
We need a plan to ensure that invoice numbers, client IDs etc do not clash.
Please state your plan of attack in your quote.
UPDATE 1: We will need non-expired credit cards to be migrated as well. We do not want expired cards in the system to be migrated.