View ECS PO in ECC after SRM system is changed

Hello Experts,

Our system SRM 3.0 ( XYZ) , ECS scenario, PO is getting replicated to ECC 6.0.( ABC)

Now we are implementing SRM 7.0 ( New SRM 7.0 box - YEE) with same ECC 6.0 ( ABC) box  mentioned above.

We are migrating open PO's to new SRM 7.0 box with new PO number ranges in SRM and ECC.

Now the Question is business need 5 years of PO data to be viewed via ME23N in ECC when SRM 3.0 no more exist, will there be a technical limitation to view old PO in ECC when SRM 3.0 system no more exist.

Again Business just need to view the old PO's in ECC 6.0, no GR. IR will be performed.

Regards

Ratha