Re: Eidgenoessische volksinitatve
Once a Volksinitiative has been "eingereicht" (issued?) the 100k signatures must be collected and handed over to the Bundeskanzlei within 18 months.
I think rules for Bundesrat and Parliament are the following:
The Bundesrat has one year to deliberate (one and a half year if they decide to present a counter-proposal) plus to issue the "Botschaft" (assessment? tidings?). Discussions by the parliament are allowed to take up to 2.5 years (3.5 years if there's a counter-proposal). The public vote has to take place no later than ten months after the parliament is done discussing.
So all in all it the vote should happen no later than 6 years after an Initiative has come about.
However, I think these terms are not absolute, more on the strong "should" level as I'm not aware of how either Bundesrat or Parliament could be "punished" if they're late.