I just spoke with the office of FastJet and it turns out that they will not be flying Kilimanjaro to Zanzibar during the low season. That means that they will not have any flights on this route after Feb 1st, 2014.
There is mixed info as to when the flights will restart. One person in the office told me they would restart on April 1st. But I find that hard to believe because April and May are the very low season. Another person told me it would probably restart on June 1st, but since they only make the routes available 90 days in advance, that will not be confirmed for a while.
I am surprised that FastJet did not put out a press release when they made the decision. This has been done in a way that will lower the level of confidence that people have in the company. I just hope that those that had booked tickets for Feb have already been informed so that they can make alternative arrangements.