Battlefield Heroes, Battlefield Play4Free, Need for Speed World, and FIFA World are set to disappear in three months. According to the site for one of these games, Battlefield Heroes, that corresponds to Tuesday, July 14th, 2015. The other three might be plus or minus a little bit, but it sounds like it will be a simultaneous shutdown. Refunds will not be provided, even if you have premium credit remaining unspent on your account. I guess that means that you should burn whatever you have left over while the servers are still running; EA will not accept new accounts or payments though.
The announcement, made by Executive Vice President of EA Studios, Patrick Söderlund, assures players that other EA free-to-play titles are growing in player base and content. He uses Star Wars: The Old Republic as an example, which will receive updates over the year, including ones that build on its narrative.
But this is one of the problems with “free-to-play” and other genres with an authoritative online component: timed life. These titles are not going to be critiqued and celebrated in University courses over the upcoming decades and centuries. It is a difficult balance. On the one hand, it is interesting to create a universe that evolves and possibly mutates based on player interaction. Those experiences disappear though (and so does the money you tie into it). That doesn't mean “don't play them” — just be aware what you're investing your time, money, and self-expression into.