[Koha] Koha 3.4

Dear Koha Community, Need help. I have only just been appointed as Librarian to a Theological library and we have just installed Koha 3.4 to automate the collection and as of last week I have started cataloguing the 15,000 resources that we currently have. I need technical advise whether I should install the latest Koha 18 version or continue with version 3.4 and upgrade later. Luisa Korodrau