When the upgrade is complete, by default, charts will be cached for 12 hours.
As you can see in the following screenshot, you can view whether a
chart is cached from the overflow menu, and you'll have the option to
force refresh it.
time that any given chart will be cached is configurable via the "edit
chart" menu item. For example, set the cache timeout to 3600 seconds for
data to cache for an hour.
to this email or reach out to razzi or the #wikimedia-analytics IRC
channel if you have any questions or concerns about this migration. As
always, the maintenance schedule can be viewed here