How to inform user that change will take time to reflect?

A form edit page works on the following logic:

If number of changes made during edit > original inputs, it can take up to 30 days for the changes to be reflected on the UI.

If the number of changes is < original inputs, it can take up to 7 days for the changes to be reflected.

How should I convey this message to the user? Is "You have made some changes. It can take up to 30 days for the change to be reflected on your interface." a good message?

I'm primarily confused about 2 things:
1. Should they be informed about the logic behind the ETA?
2. Is "...change to be reflected on your interface" an understandable phrase? Even if the user a is non-native english speaker?