FR24 say the return flight was intended to go via WDH but instead diverted to ERS?
It's pointless to attempt winning internet debate. 求同存異. よく見て・よく聞いて・よく考える (≧▽≦) Nyan! Nyan! Nyan! Nyan! Nyan! Nyan! Nyan! Nyan! (≧▽≦) Meow Meow Meow! Meow Meow Meow Meow! You are now at your youngest moment in your remaining life.
As the link provided by MoKa777 says a tender to provide a scheduled service is currently out.
Elsewhere it has been stated that tenders must be submitted by 'Summer 2017'. The tenders will then be considered and one hopefully chosen.
I guess that a proposed starting date will be part of each tender. This is likely to vary from operator to operator depending on their actual current situations. This might include the availability of the proposed operational equipment and any change to its cabin configuration. Here also note that the original Comair proposal of a once-weekly service required an engineer to travel on every flight. It also required the establishment of an appropriate spare parts stock on the island. So organising such a supply and transporting and locating it on the island prior to the inaugural scheduled flight could be but one of many issues to be addressed.
Wake up to find out that you are the eyes of the world The heart has its beaches, its homeland and thoughts of its own Wake now, discover that you are the song that the morning brings The heart has its seasons, its evenings and songs of its own