Prepone is a great word - it's the opposite of postpone. When you prepone a meeting, you change its scheduled time so that it occurs sooner than originally planned. Has his usage spread beyond India? Would other English speakers understand it?
IN India, people created the word “prepone” as the obvious opposite of postpone. On the Internet, a form of cyber-English has sprouted with such words as “net-surfing.”
(I hope it surprises no one that this citation is from 1995—eons ago in Internet time).
More recently, in 2008 the Monitor published this article discussing prepone in much more detail.
So it does not appear that prepone has much currency outside of India. I have heard it in my day-to-day business on occasion here in the United States in the software development industry—from my colleagues from India.
The New Oxford American Dictionary I had on my Mac Mini didn't report prepone as an existing word. The Oxford Living Dictionaries says that the meaning of prepone is:
[Indian] bring (something) forward to an earlier date or time.
One of the examples it shows is the following.
The publication date has been preponed from July to June.
It also says its origin is early 20th century.
Wiktionary also reports it is only used in India (or that is chiefly from that country).
OED explains that the etymology is from the classical Latin word praepōnere:
pre- and pōnere- to place
This gives the word its (now) obsolete meaning of to place in front of or to set before. The later use of this word to refer almost exclusively to placements in time is said to be most frequent in Indian English.
Thus contrary to popular belief it is not an Indian neologism but has Latin roots similar to the well known antonym.