Some publishers of e-journals place restrictions on access to the current year's content, this is called an embargo.
You can view potential embargoes for the title you wish to access by going to the eJournal Search in the Library Catalogue and performing a title search.
Please note that the eJournal Search lists all titles that the University has a subscription to or titles that are freely available on the Web. Titles that you may come across when searching across publisher's web sites are not necessarily subscribed to by the University.