EASA document from Feb 2016 allegedly states that electric trim would not work above 230 knots. That might explain why they re-engaged trim (if the indication that they did re-engage trim is correct)...
The undated EASA certification document, available online, was issued in February 2016, an agency spokesman said.
It specifically noted that at speeds greater than 230 knots (265mph, 425kph) with flaps retracted, pilots might have to use the wheel in the cockpit’s center console rather than an electric thumb switch on the control yoke.
https://www.reuters.com/article/us-e...-idUSKCN1RA0DP