Trouble using timestamps in variables

Hello. I’m unable to use a variable for a timestamp and would appreciate any advice. Is this a bug or am I doing something wrong? The screenshot below shows my trouble. I created a variable called ‘lineage_version’ in order to select from the ‘date_appended’ column of my table (underlined in red). This column’s type is timestamp. When I copy a value from the table (red circle in bottom right) and paste it into the variable box (red circle on left), the value gets truncated. This is not a problem with copy/paste, because the full value shows up briefly before I move the cursor out of the variable box.

Please advise.

Note: I found a workaround. If I cast the ‘date_appended’ column as STRING, the variable works as expected.