Is there a set date for the retirement of Hubble Space Telescope from service?

I am working on a paper on the history and accomplishments of the Hubble Space Telescope, and I need to know if there is an actual set date for when HST is going to be retired from service. There is no information directly answering this question in either NASA's website or the Space Telescope Science Institute's website. I can't seem to find any definite answer any where. If anyone knows whether or not there has been a concrete decision, I would appreciate it if you could let me know and direct me to a reputable online source for information. Thanks so much!