Not that it is difficult to create one manually, but it would be convenient to have a rule event for when an customer updates and address (or sets default). Just a suggestion
We already have events for customer update/insert but we don't have an event when setting an address as "default", You could propose a patch or I'll write one if other people are interested. Let's postpone that for now
I'm interested as well. As somebody already worked on that, or should I start from scratch? And in that case, is there something I should know to have a chance to have the patch committed at my first try (event naming, ...)?
Linking to #2387929: Add a hook when an address is set as default which provides invoke for a hook on a profile being marked as default.
Working on this now.
Updating issue title
Issue #1839734: Rules event on profile default change
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