That's the same schedule as shown on the Bahn website. It's not the only connection to the airport, just the quickest one.
Note that Pasing is a main connection station on the west side of Munich. There you change to an S8, which goes entirely through Munich (underground) and then goes to the airport from the east side of Munich. You will have a seven minute, one platform change in Pasing. Here is a layout of the station.
You can also take any S-Bahn from Pasing to Laim (the next station towards town) and catch the next S1 to the airport. That will take 11 minutes longer, and has two changes, but you will have more time to make the connections. To see this connection on the Bahn website, click "show details", then "adjust the transfer time", and select "leave later from München-Pasing". You'll actually have 30 minutes, total, to make the two connections at Pasing and Laim. The suggested connection has 20 minutes in Pasing with a platform change, then a 10 minute, same platform change in Laim.
Or, you can stay on the train to the Hbf, then find the "tief" (deep) S-Bahn station, and take either S1 or S8 to the airport.
My advice would be to try and make the seven minute connection to the S8 at Pasing. If you miss the S8, take one of the next S-Bahns to Laim and catch the S1 at 12:31.
The S1 goes to the airport from the west side of town. It diverts from the mainline at Laim and does not go through Pasing. If you take the S1, note that it splits in Neufahrn, with the front end of the train going to Freising instead of the airport. Board near the back end of the train.
