I do not restrict anyone and I use the slots. I have no routes currently unscheduled and I do not oversupply any route. When I was rearranging my long haul schedule to 7-day-scheduling yesterday, I used Strasbourg to block the slots in Paris so I would not lose one of a set and screw up the scheduling again, as long hauls over a certain range cannot be created as a daily route under a single flight number.
I closed the routes to Strasbourg again quite soon, as I progressed to reschedule. I however did not release the slots as I did this (as releasing them releases both the destination and origin slots, while I needed the latter). The slots will only be returned to the pool after the normal expiration time.
I am sorry if this caused any inconvenience.
The problem is that you can's select that you want to keep only one set of slots and not the other. (See a Feature Request on this subject).
So the CDG player ended up with a bunch of orphan Strasbourg slots in his possession. I don't think it was intentional. The system clears these orphan slots that were never flown very quickly (1 month I believe). So you will see your slots back within 1 game day...
This is exactly what happened. I will select an airport with no airline based there next time, I did not take this into account and was rather inconsiderate about it, for which I apologize.
'In summary, airline is not allowed to create "placeholder" routes to obtain slots to use them later or to restrict competing airlines.
This is correct. As I did neither, I am not aware of any wrongdoing on my side. I either rearranged and rescheduled immediately or did actually fly the routes I created.