Is your feature request related to a problem? Please describe.
I enable caching feature after my app already runs on production for some time. Because of that, the caching value doesn't reflect the true number

Describe the solution you'd like
A method/rake task to recalculate all caching values

For travel albums or for any event, pictures modification time does not reflect the event timeline.

It happens a lot that pictures are modify (cropping, enhancements, etc.), and changing their orders does not help readability.

Could the creation date be the default info used ?