How to setup Manual and Automatic Sequencing for Sales Order at the same time

Hello All

We have a requirement to create Sales Order in 2 ways for the same Order Type while using Order Import for both cases

First--> Automatic Generation of Sequence

Second-->Manual Generation of Sequence

We have a valid business scenario - Where we have a third party system - where orders are generated. So we want to create those orders in EBS with the same SO Number.

However, at the same time, we want to keep on generating the orders in EBS manually.

I am aware about Manual and Automatic - one at a time. So, please suggest any way to achieve dual type of sequencing at the same time as per the data in the OE Interface.