Determining end of plugin render frame

I recently updated tracktion after not having done so for a year or two. Plugin rendering used to use the AudioPlaybackContext instead of PluginPlaybackContext; when using the former, I was able to use the members to determine the end time (in edit time) of the frame. I still need to do this, but it seems like the latter doesn’t have the members to support this. (I could try to use the buffer length in samples and the provided start time to calculate, but I don’t have a sample rate from the context either.) Any advice on how I might be able to calculate this end time now?

I’ve made it a TimeRange on develop: