Morning Dave,

Thanks for your above comment, I'm not sure if it is my use of bad terminology or my understanding of what would happen, but in the below screenshot if a change was made to the Database instance it could then have an impact on any of the CIs below (my understanding of downstream) i.e. something wrong with the database could cause the environment to stop working and therefore all the services within the environment?

Any help on where my knowledge is lacking or misplaced is greatly appreciated.