Dear Maintainer,

According to the man page, "If you specify a job to absolutely run at a
specific time and date in the past, the job will run as soon as
possible.  For example, if it is 8pm and you do a `at 6pm today`, it
will run more likely at 8:05pm."

However, when one attempts to do this in practice, the command fails
with an error "refusing to create job destined in the past":

```
$ date; echo echo test | at '13:00 today'
Thu  6 Jan 13:49:42 GMT 2022
at: refusing to create job destined in the past
```

I had expected the above commands to successfully create a job, run the
command "echo test" immediately, then immediately email me the output
(i.e. an email that just contains the word "test").