Excuse my ignorance, but isn't Whatsapp encrypted end to end? The only information available to Facebook is meta-data, who I was sending to, what time, response

Excuse my ignorance, but isn't Whatsapp encrypted end to end? The only information available to Facebook is meta-data, who I was sending to, what time, response time, etc. Is there anything I'm missing? If not, how does Signal deal w/ meta-data?