While normally the job is executed when the time/date specification fields all match the current time and date, there is one exception: if both "day of month" and "day of week" are restricted (not "*"), then either the "day of month" field (3) or the "day of week" field (5) must match the current day
Por isso, acontece apenas em junho, às 13:35. Além disso, ele precisa ser no dia 15 de junho ou no sexto dia da semana. Ambas ao mesmo tempo funcionarão também.
A execução de man 5 crontab
fornecerá algumas informações adicionais. Recomendamos que você use test
para especificar os dois uma data específica e restringir o dia da semana:
Note: The day of a command's execution can be specified by two fields — day of month, and day of week. If both fields are restricted (i.e., aren't *), the command will be run when either field matches the current time. For example, ''30 4 1,15 * 5'' would cause a command to be run at 4:30 am on the 1st and 15th of each month, plus every Friday. One can, however, achieve the desired result by adding a test to the command (see the last example in EXAMPLE CRON FILE below).
[...]
# Run on every second Saturday of the month
0 4 8-14 * * test $(date +\%u) -eq 6 && echo "2nd Saturday"