How to run upgrade step (for plone.app.event)?

Question

The plone.app.event documentation says:

If you want to upgrade Products.ATContentTypes based ATEvents to plone.app.event ones, there is an upgrade step for that: "Upgrades old AT events to plone.app.events" (Metadata version 1 to 2).

However, where do I find this upgrade step and how can I run it? I installed plone.app.event 1.0.4 using plone.app.event [archetypes, ploneintegration] in buildout.cfg as described in the documentation. Then I added it to the plone instance via the plone_control_center. But afterwards all old events are gone and I cannot find a way to upgrade them.

Answer 1

Documentation is not very clear, but probably you must directly access the portal_setup tool in ZMI, then go the the "Upgrades" tab and select upgrade step from there.