On-Premise Gateway - Web Data Sources Credentialing Issue

Hello everyone! I am managing my organizations Power BI Gateway and have run into a snag that is manageable now, but will not be soon.

Our customers prefer to use Excel files as the primary data sources for the report published the Power BI Service and consumed by their audience. We have encouraged them to use database sources, such as Oracle, but it continues to fall on deaf ears. These Excel files are then stored in a SharePoint folder. There are mulitple files and multiple SharePoints needing to be accessed. I've setup the gateway data source type as 'Web' and entered in the URL for the Excel file. The URL is obtained by opening the file from the SharePoint, selecting 'File', 'Info' and 'Copy Path', and removing the '?web=1' from the end of the URL. 

My issue comes to credentialing. I've selected 'OAuth2' for 'Authentication Method' and use my company credentials to sign in as I am authorized for each SharePoint so that Gateway can pickup the data for the scheduled refreshes. The problem comes in when I need to change my password per security policy. When my password changes, all of the data sources lose their connection in the gateway because the credentials now fail. As of now, we are just short of 30 web sources; although it is a pain, it is not insurmountable to go through each one and update the credentials. This will not be the case for much longer as Power BI is growing in popularity rather quickly in my company and more customers would like to use the scheduled refresh feature.

Any suggestions on what I can do?