Clearing Forum & Blog Subscriptions For Users Via The REST API

I'm looking to bulk unsubscribe users from Forums (and Blogs ideally too) using the Rest API.

I can see there is an endpoint that might allow me to do this but it doesn't say what the parameters are:

https://community.telligent.com/community/10/w/api-documentation/61437/set-subscription-application-subscriptions-rest-endpoint

If it requires me to send an userid, application id and flag to subscribe/unsubscribe, this isn't going to be great as I will have to loop over all users and all applications.

Ideally I'd be able to send no application id and clear all subscriptions for a user.

I also saw some issues reported with this here:

https://community.telligent.com/community/10/f/ask-the-community/1145580/get-list-of-users-subscribed-to-blog-via-rest

If none of this is possible then are my only options to run an DB Script, e.g:

delete from [te_Blog_BlogSubscriptions]

delete from cs_TrackedSections

delete from cs_TrackedThreads

Although I'm not sure where Forum thread and forum subscriptions are tracking in v10 as these tables don't seem to exist in the DB now. Have they been renamed/moved?

Any advice on this would be much appreciated.

Thanks

Adam