When you use getParam with a list of timeranges, the scientist's recent timeranges are shown and not the list of timeranges. Try:
trs=['2020-207 00:00 to 09:00','2018-197 03:00 to 07:00' ]
tr= getParam('timerange', '2020-207 00:00 to 09:00', 'time range', trs )