If the early admin or SOP, products are changed, the existing project would be obstacles for better organization and info creation. They no longer serve as a good representation or functional divisions for the company. If the user doesn't have right keywords for the filter, he won't be able to find his tickets easily.
One of the easier solution is to use Trello as a general medium to organize the tickets in different projects. This can also help team lead to visualize and prioritize tasks/tickets at hand. Trello is not a ticketing system and it does not serve well as one. But it does well when collecting and prioritizing tasks (each with several tickets, possibly).
Maybe I will have to use this method to bridge companies with different ticket systems (Jira, Trac, mentis...). This can also save time and generalize the flow for all participants.