Hi, Christopher.
Event Aggregator (EA) will import events but not tickets, since tickets are not supported by the iCalendar spec.
If an event is edited at the source (where importedĀ from), the event EA creates in WP should simply receive theĀ event updates (e.g. modified event description) and the tickets shouldn’t be affected at all.
With everything, I’d suggest testing it to see how it works for your own needs to make sure before implementing site-wide.
Please let me know if you have any follow-up questions on this topic.