Turns out, this was broken since we added support for a default top timeframe. That value was overriding the date of the user’s previous visit instead of just being a default value when there was no previous visit (new user or anon).
While at it, I noticed another bug where a returning user would not be redirected to the proper timeframe due to a variable not being named properly on the client-side… 
Thanks @P16 for the report as we got to fix 2 bugs 