FR: Select multiple entries at once for discount / sales rules

[Mathias-Syversen]

We have a pretty big commerce site that has a custom entry type for "store", the site ships to 1100+ stores in their network.
Some times, the client would like to do a discount, where certain stores have a 30% discount, but not all.

Each order has an entry field for selected store, you select this store at the beginning of ordering, to see relevant products.

I can set up a sale, and say it applies for orders related to a certain store, but this rule only allows for 1 entry.
Setting up a rule for 300 stores would take some time, and be hard to maintain.

Would it be possible to update this to allow multiple entries to be selected at once?
In the screenshot below "Valgt butikk" is a custom entry field on the order.

[lukeholder]

The "Related to" rule allows multiple elements:

Would this work for you?