last -t does not work as what man page said

The man page of the last command says as follows:

-t YYYYMMDDHHMMSS
              Display the state of logins as of the specified time. This is useful, e.g., to determine easily who was logged
              in at a particular time -- specify that time with -t and look for "still logged in”.

However, Wen I ran the command with -t, I got the following output:
# last -F -t 20150107000000 | grep pts
root pts/2 jp001.solidtunne Tue Jan 6 18:39:05 2015 - Tue Jan 6 18:40:34 2015 (00:01)
root pts/2 jp001.solidtunne Tue Jan 6 18:37:24 2015 - Tue Jan 6 18:37:41 2015 (00:00)
root pts/2 jp001.solidtunne Tue Jan 6 16:42:33 2015 - Tue Jan 6 16:43:49 2015 (00:01)
root pts/2 jp001.solidtunne Tue Jan 6 13:03:26 2015 - Tue Jan 6 13:07:02 2015 (00:03)
root pts/2 jp001.solidtunne Tue Jan 6 09:03:24 2015 - Tue Jan 6 09:03:54 2015 (00:00)
root pts/2 jp001.solidtunne Tue Jan 6 04:53:54 2015 - Tue Jan 6 04:54:07 2015 (00:00)
root pts/0 42.243.9.2 Mon Jan 5 03:06:48 2015 - Mon Jan 5 03:07:10 2015 (00:00)
root pts/2 42.243.9.2 Sun Jan 4 14:08:02 2015 - Sun Jan 4 14:09:02 2015 (00:01)
root pts/1 42.243.9.2 Sun Jan 4 12:09:56 2015 - Sun Jan 4 12:10:05 2015 (00:00)
root pts/0 42.243.9.2 Sun Jan 4 03:24:57 2015 - Sun Jan 4 03:25:10 2015 (00:00)
root pts/2 42.243.96.183 Sat Jan 3 14:47:38 2015 - Sat Jan 3 14:47:54 2015 (00:00)
root pts/4 sf003.solidtunne Fri Jan 2 15:23:12 2015 - Fri Jan 2 15:23:51 2015 (00:00)
root pts/0 hk000.solidtunne Thu Jan 1 16:40:55 2015 - Thu Jan 1 16:41:21 2015 (00:00)
root pts/2 hk000.solidtunne Thu Jan 1 15:41:52 2015 - Thu Jan 1 15:42:02 2015 (00:00)
root pts/4 hk000.solidtunne Thu Jan 1 11:24:56 2015 - Thu Jan 1 13:40:40 2015 (02:15)
root pts/4 hk000.solidtunne Thu Jan 1 11:24:34 2015 - Thu Jan 1 11:24:48 2015 (00:00)
root pts/0 hk000.solidtunne Thu Jan 1 08:31:13 2015 - Thu Jan 1 08:31:25 2015 (00:00)

The current date is as follows:
# date
Thu Jan 8 08:12:32 UTC 2015

And Ubuntu version:
# lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 14.04.1 LTS
Release: 14.04
Codename: trusty

Kernel:
# uname -a
Linux install 3.13.0-40-generic #69-Ubuntu SMP Thu Nov 13 17:53:56 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux

So, it seems the -t actually returns the state of logins up till the specified time, as opposed to as of the specified time as written in the man page, or am I missing something?