Hi, I have a lot of relations (boundaries) that I would like to be noticed when they have a change in their members. Is there a tool for this?
You might want to give OSMarelmon a try.
It’s a student’s work at University of Passau. You can add simple queries via key-value pairs and you’ll get a rss-feed which tries to check your query 2 times a day afair. However, I’m not sure if it works with a large set of huge relation data 
Give it a try and I’d be interested in feedback 
Thank you very much, I’ll have to add some tag to the boundaries relations so I can check them together, and then I give you my comments.
I have been tagging the boundary relations that I made with
is_in:country
is_in:country_code
is_in:state
is_in:state_code
Maybe the same keys are useful for you.