How would offline_access work after deprecation after May 1st?
Error Domain=facebookErrDomain Code=10 "The operation couldn’t be completed. (facebookErrDomain error 10.)" UserInfo=0x1404bb70 {request_args=(
        {
        key = method;
        value = "auth.extendSSOAccessToken";
    },
        {
        key = sdk;
        value = ios;
    },
        {
        key = "sdk_version";
        value = 2;
    },
        {
        key = "access_token";
        value = AAACiLiBjLHABAOo3NZCSSLlRddFZCQUsky0q9sogtzHIFGpNNoeYUqtt2X2QUvxMg8AwsQqSLP3oe0cxUoLIXwVZC3xDGuBC3QOvFgELwZDZD;
    },
        {
        key = format;
        value = json;
    }
), error_code=10, error_msg=The access token was not obtained using single sign-on}

https://graph.facebook.com/oauth/access_token?
        client_id=APP_ID&
        client_secret=APP_SECRET&
        grant_type=fb_exchange_token&
        fb_exchange_token=EXISTING_ACCESS_TOKEN