Host SAPUI5/OpenUI5 bootstrap - Licensing

Hello All,

We want to start developing SAPUI5/OpenUI5 apps to our customers. Unfortunately, they have older versions of the Fiori Front End Server (FES). At most they have FES 3.0, but some are still on FES 2.0. Upgrading the FES is not feasible at this time.

Due to security considerations, they also cannot use cloud services, so developing on the SAP Cloud Platform is sadly not an option.

We thought about copying the newer versions of the SAPUI5/OpenUI5 bootstrap code and hosting it on-premise. Are there any licensing issues we need to consider?
For example, for SAPUI5, it is my understanding that its license is (among other options) included in the license for the SAP_UI component. However, does that mean that if we have an server with SAP_UI installed, no matter the version, we can use whatever version of the SAPUI5 bootstrap?
For OpenUI5, even though it's open-source, can we copy the code and simply host on-premise, or do we need to get approval from SAP first?

Thank you,
Guy.