Do we have to delete old obb data when pushing updates?

Hello,

I'm currently at work and don't have my device to personally test this but my boss wants me to brain storm our logic so please excuse what could be a dumb question;

So under the developer guide Google states under rules and limitations:

"When updating an expansion file manually, you must delete the previous expansion file."

The structure of obb files are [main|patch].expansion-version.package-name.obb

I plan on downloading my obb file from my server.

With that being said, if I publish my app with with my expansion-version as 1, it will download it obviously as the first ever. When I publish a new update or something and it becomes 2, will I have to delete the obb for 1?

I know I probably don't HAVE to, but will the files just accumulate up on the users sd card?

I know that the expansion-version has to correspond with your app version as an FYI.

The developer guide also states that you can only EVER have one main file, so does that mean Android will automatically delete the old one or does that mean that when I try to save a new version it will get denied?

Thanks.