Asobinet reports that the Leica DG 100-400mm has been discontinued. As of now you still can get this lens in Stock at Amazon US&EU and BHphoto. But I guess it will be soon sold out 
Sad to hear that. I’ve read that Panasonic hasn’t been able to repair this lens for a while now. Instead of repairs, a discount voucher for a new lens is given.
Between the discontinuation of the PL 100-400, the 200/2.8, and the reported scarcity of the teleconverters, it really does seem that Panasonic is pulling out of the wildlife niche for m4/3. A real pity, as that is an area where m4/3 excels.
Interesting. This lens is still showing in Panasonic USA’s lens lineup.
Usually, “discontinued” does not mean “unavailable”. PL 100-400’s will be sold until there are no more units left.
Hopefully, given the rumors that a G9 successor will be announced in the near future, Panasonic will release a 100-400 Mk II.