There is one sort of information almost everyone leaves behind them, namely the memories of people who knew that person when she was alive. By definition, there is no information theoretic bound preventing reconstructing a person with such precision that everyone who knew her won't be able to tell the difference. Similarly, there is no information theoretic bound preventing reconstructing a person that writes novels which the original version could have written, as far as the readers can tell. So, if we launch FAI tomorrow we can get a version of Pratchett sufficiently close to the original to "fool" his wife, daughter and fans. On the other hand, there might be stronger complexity theoretic bounds: reconstructing a person to fit a given set of "output" is a problem which is a priori only known to be in NP.