Currently the fine name is generated at the beginning of the recording. If you want the phone number be part of the file name, then it has to be available right from the start.

Two things are currently on my todo list. One, find out how to get the phone number. Two, figure out how to make a friendly UI that would allow to specify start/end/length date/time of the recording for the file name generation. The latter sounds simple enough but I would like to have the possibility to have both in the same string, so you can have files like 2014-04-11-From_0911-To_0927. Unfortunately I am running out of letters in the %<letter> notation.