Add Havana (Cuba) to your list and use my-locations table to visually convert it's time to another timezone or city time.
Mouse over the colored hour-tiles and glance at the hours selected by the column.

Current time zone for Havana (Cuba) is CDT, whose offset is GMT-4 from Greenwich Mean Time (GMT).

The IANA timezone identifier for Havana, Cuba is "America/Havana"

DST started on Sunday, March 9 2025 at 0:00 am local time, when time in Havana moved forward 1 hour to 1:00 am.
DST ends on Sunday, November 2 2025 at 1:00 am local time, when time in Havana moves back 1 hour to 0:00 am.