I'm resurrecting this thread because this has been driving me nuts for at least a month. I know this worked at some point on my Lumia 1520 (which is at Nokia Care for repair right now). I also have a Lumia 520 that has DP version 8.1.14157.200 and the suggested place search absolutely works in the calendar. I have screenshots below.
DISCLAIMER: The calendar app (as far as I know) is now a separate app and not OS dependent. Everything below is going on the assumption that the DP has something to do with this not working. It could be that the Calendar app enabled then subsequently disabled this feature during app updates.
EDIT:
So this is weird. Strictly updating the DP from 14157.200 to 14203.306 did not break suggested places (See below images)
EDIT 2:
I restored the 520 factory image from lumia software recovery which is 8.10.12393.890 and suggested places does not work (as I'd expect).
EDIT 3:
I re-enabled DP and the first update, 8.10.12400.899 did not enable or add suggested places.
Note: this came through as a critical update.
EDIT 4:
The next DP update had two versions, 8.10.14147.180 & 8.10.14157.200. The suggested places is still not enabled. This is really strange. I wonder if it has to do with some updates coming down as critical updates.
Note: This update came through as a critical update also.
