Compatibility between ECC 6 EHP 8 AND BW 3.5

Hello,

I would like to clarify if there could be any problem with BW, if the current version is BW 3.5 and we are reviewing these two options to move in ECC:

1. SAP ECC 6.0 EHP 4 (sp5) -> SAP ECC 6.0 EHP 8 (sp6)
2. SAP ECC 6.0 EHP 4 (sp5) -> SAP ECC 6.0 EHP 4 (sp19)

I read that EHP 8 is Unicode and BW 3.5 is not Unicode, could this cause errors? is there any solution for this or this will require to move to BW 7.0?

Thanks and regards

Txaro