The Honolulu Advertiser reports that Go! airlines and Island Air have reached a tentative code-sharing agreement for flights between Kahului and Hilo, as well as Kahului and Lihue. Mesa Air Group, go!'s Phoenix-based parent, said it hopes to expand the code-share agreement with Island Air once a separate code-share pact with Mokulele Airlines expires on April 28. Go! currently has a code-share agreement with Mokulele, dubbed go!Express, for flights serving smaller interisland routes such as Kona and Kahului, Kahului and Kapalua, and Kapalua and Honolulu. That service has been on the rocks since last November when Mokulele partnered with Indianapolis-based Republic Airways to compete head-on with go! on its main interisland routes. Go! and Island Air could launch the new Kahului to Hilo and Kahului to Lihue code-shares in the next several weeks, pending the completion of a definitive agreement.