Hi @JDU ,
That makes total sense. Using a Learning Plan as a dynamic "notification profile" so you don't have to manually update the notification settings for every single course is actually a really clever workaround!
Regarding the error: it is highly likely that your Learning Plan has simply grown too large. When you add a new course to it, Docebo has to instantly recalculate the progress and enrollment paths for every single user inside that plan. The system is probably failing to finish that massive background job, which results in Error 41.
Since this setup has worked well for you up until now, the fastest fix is to simply create a new Learning Plan. Set up your new LP with the exact same notification rules, and start dropping your new courses into that one instead. This will reset the background processing load while keeping your admin workflow exactly the same.
In organizations I've worked with, when native notifications become too rigid or cause platform strain like this, we usually move the automation entirely outside the platform using Docebo Connect. You can set it up to listen for enrollment events and then dispatch the emails directly through your organization's Outlook or Google Workspace. This gives you total control over the process without bogging down the LMS.
You can explore the Docebo Connect capabilities here: https://help.docebo.com/hc/en-us/sections/4408160858130-Docebo-Connect
Let us know what Support says on Monday!