Well, this will really depend on your child and his/her ability to adjust to their new surroundings. Some children need a lot longer time to bond with parents and to get used to a different surroundings - others take less time.
Our son adjusted remarkably well to his new environment upon returning home, so we could have probably taken a vacation a month or so after returning; however, I can tell you that my wife and I were exhausted (both physically and emotionally) after returning home and it took us about 3 months or so for things to get back to normal for us.
You may need to wait to see about all these factors before planning a trip in advance.
Good luck!
