Undo a not completed Release Update?

Hello,

Our customer has a modification to Identify Serials with Serial Scan, but the scan performance is limited due to the single processing of each scanned barcode.
In 26R1 there is a new functionality to improve the performance by deferring serial validation until the entire list is saved.

The customer is eager to see the performance with the new functionality and if the new functionality is working with the already implemented modification (or at least with slight changes, without having to redesign the whole modification).

As it seems to be impossible to test this process on a reference environment as we are not able to connect scanners, we are searching for other options.

So what came in our mind is to start the Release Update Studio and process until we can create at least a topic environment to then be able to test the functionality's performance and how it interacts with the existing modification.

But if the performance is not that better as customer expects it to be, or if the interaction with the existing modification is not working and a complete redesign of the modification would be needed, we would like to just undo everything done in the Release Update Studio and leave the BuildPlace at the actual 25R1 version and later do the Release Update 26R2.
We would then be able to plan the redesign of the modification and the full process testing accordingly.

Is it possible to undo what was done within the Release Update Studio and if so, until which state would it be possible?
Maybe it would even be possible after creating a delivery to do the testing on the customer's STAGE environment (which would of course be set up newly in case of undoing) but before completing and merging the RU into the BuildPlace?

Thanks for every kind of information on this!

Best regards,
Stefan