Today, 29th of March 2020, DST went into effect for my time zone (Europe/Amsterdam), using legacy time zone results in wrong values for TIME WITH TIME ZONE values.
Use CONNECT or CREATE DATABASE to specify a database
SQL> connect 'localhost:employee' user sysdba password 'masterkey';
Database: 'localhost:employee', User: SYSDBA
SQL> set bind of time with time zone to legacy;
SQL> select CURRENT_TIME, LOCALTIME from RDB$DATABASE;
I would expect that CURRENT_TIME and LOCALTIME to yield the exact same value in this case.
This incorrect behaviour only occurs on the date of the DST change: after changing my computer date to tomorrow (30th of March 2020), both had the same value.