After the launch of AirlineSim 1.5, we were made aware of some problems with Traffic Rights as applied to the improved via-flight feature. In short, the second segments of any such flights that didn't have traffic pickup rights were running empty, regardless of any passenger demand between the origin and the final destination. Happily, the cause of the problem was easy to find - an important part of the new AS1.5 flight system had not been made to take via flights into account.
Fixing the bug was simple, but fixing it also presented an opportunity to add a new feature, which AirlineSim has so far been missing. In real life, some airlines operate 'mini hubs' at airports abroad; examples include operations by South American airlines in Spain, European airlines in Florida or American airlines in Asia. The airlines have the ability - assuming no additional agreements exist between the second and third countries - to carry passengers from Country A to Country C with a change of flight in Country B without picking up additional passengers in B, effectively enabling them to create connection-based networks at airports outside their own countries. This ability will now be available in AirlineSim, too - hence the 'feature' part of today's title.
Operating a 'mini hub' is not for the faint-hearted; airlines still won't have the ability to carry local traffic on the second leg of the flight, so the advantages - and costs - of operating these extra flights will have to be considered very carefully, and in many cases it will be more efficient to make use of a local partner to carry any connecting traffic, but the option will be available for those situations where such partners are unavailable or unattractive.
It's worth noting, in addition, that the via flight function only needs to be used in situations where 5th Freedom rights are available for onward flights; for example, between countries which are parties to the Yamoussoukro Decision. If 5th Freedom traffic isn't a concern, regular flights that aren't explicitly via the intermediate point will also work fine. Of course, you may want to use the feature anyway - using it saves a flight number, and will probably offer the possibility of a dedicated technical stop in the future.