I have a complex custom two-year reading plan. It was too complex to create in one sitting, so every few months, and add another bunch of readings to it, always trying to keep ahead of the current date.
Last week, I thought it would be useful to share with my church, so changed the list so it was shared with them. However, having done so, I can no longer edit the reading plan.
I'm not sure why that limitation exists, but more importantly, I should not have lost editing rights without being warned that would happen. My carefully curated reading list is now permanently stuck, unable to be extended — which after 18 months of nurturing is frustrating, to say the least.