[tz] Chile TZ rule 1942 June superfluous?

[Alois Treindl]

I do not understand the purpose of the line for June 1942 in the Chile 
rules:

# Rule  NAME    FROM    TO      TYPE    IN      ON      AT      SAVE 
LETTER/S
Rule    Chile   1927    1932    -       Sep      1      0:00    1:00    S
Rule    Chile   1928    1932    -       Apr      1      0:00    0       -
--> Rule    Chile   1942    only    -       Jun      1      4:00u   0 
     -
Rule    Chile   1942    only    -       Aug      1      5:00u   1:00    S

Chile was on GMTOFF -5h from 1927 to 1947.

What purpose has that line which does not change anything, as no DST was 
in force before that date:
Rule    Chile   1942    only    -       Jun      1      4:00u   0