The Independent cites a report from the UN Security Council finding that ISIS is preparing a "retreat zone" in Libya as coalition air-strikes (and a ground offensive by Kurdish-led forces, as the account fails to note) threaten the group's territory in Iraq and Syria. The Libyan affiliate is said to be the one ISIS franchise actually operating under the direction of the leadership in Iraq and Syria. The leadership is said to view Libya as "a potential retreat and operational zone for Isil fighters unable to reach the Middle East." The Libya franchise is said to have between 2,000 and 3,000 fighters. Franchise leader Abu al-Mughirah al-Qahtani is quoted boasting of the country's importance due to its proximity to southern Europe and its abundance of resources "that cannot dry."
Maddeningly, The Independent does not give the name of the report, the author(s), the exact date of its release, or any other such information. So we are left to wonder if this is the same report referenced by Al Jazeera and AFP as produced by a UN team monitoring the Libya arms sanctions. This report warns of potential for the franchise to expand: "While currently concentrated in its stronghold in Sirte, ISIL could seek local alliances to expand its territorial control, also entailing the risk of motivating additional foreign terrorist fighters to join the group in Libya."
A quote from al-Qahtani is offered similarly noting Libya's strategic location indicates that it is probably the same report (or at least the same quote paraphrased by The Independent): "Libya has a great importance because it is in Africa and south of Europe… [I]t is also a gate to the African desert stretching to a number of African countries."