This was actually my second attempt at creating alerts for events in game.
I built the first version as just a calendar in Google, using a third party to trigger twitter messages.
I abandonded that because I wanted to build a better custom system with the main purpose being the twitter alerts for events.
This project has had a somewhat weird evolution for it. The user facing portion has seen very little change after the initial launch with the exception of more timezones.
I built a crawler that will ping the dev tracker for Star Wars: The Old Republic, looking for game maintence announcements. When it sees these posts it will extract the patch number, start time, and end time, and make a special post to reddit.
This eventually evolved into also tracking all dev posts for reddit, adding followup posts in the same thread to the same post on reddit and ignoring anything that was too short for a single "dev posts you may have missed today" post at 7PM every day (if there is anything to post). This part is not best served by what SWTOREvents does, but only took about 20 lines of code to add to the existing system in place.
Very recently (May 5, 2016) I merged SWTOREvents (and SWTORCartel) into SWTORData. This was done on the UI side of things only, the backend they remain separate applications. I am still looking into how to expand on this merge in the future, including opening up an API.
Merged into SWTORData – www.swtordata.com