Filtering Appointments+ Backend for Service Provider


I have some custom code working as per this thread

It's a superb bit of code for me and something I think should be part of the main plugin. I'm very grateful for getting this working.

However I'd like some help taking a step further please. My Service Providers are set up as "Editors". When they log into the backend of wordpress they only see their own appointments and when they click export they can only export their own appointments. It's working great!

But it would be great that when they were booking new appointments the only service provider they could pick would be themselves and the only service names they could pick would be the ones they are linked to in the Settings>Service Prioviders set up page

Any help much appreciated. As it's just filtering I would hope it's possible

My final step would be for me to set up another user where I can choose which service providers (and therefore service names) they can see. Like a supervisor level but for now I'd be happy to just get it filtering properly!

Many Thanks