Unable to import swift definitions when installing statically

[markst]

When installing YouboraLib statically I'm unable to use swift definitions outside of pod.

target 'YouboraAVPlayerAdapter' do
  platform :ios, '10.0'

  # Pods must be build statically
  # use_frameworks! :linkage => :static

  # Pods for YouboraAVPlayerAdapter
  pod 'YouboraLib'

In the YouboraAVPlayerAdapter previously definitions are imported using:

#import <YouboraLib/YouboraLib-Swift.h>

But when installing statically the following output occurs:

'YouboraLib/YouboraLib-Swift.h' file not found

[markst]

I've tried importing umbrella:

#import <YouboraLib/YouboraLib-umbrella.h>

But it seems none of the swift definitions are exposed due to: https://bitbucket.org/npaw/lib-plugin-ios/pull-requests/206
When compiling the following occurs:

Property 'buffering' cannot be found in forward class object 'YBPlaybackFlags'