add challenge does not add new challenges for newcomers to event

[mrtrkmn]

Describe the bug
Add Challenge feature integrated to have additional challenges in the middle of an event, however it is partially acting correct. It adds challenges to existing team members for an event however it does not add challenges for others who are signing up. *(only old set of challenges are assigned to them!)

[mrtrkmn]

The problem comes when the event is just started and after immediately starting of the event, adding challenges. Since queued labs are processed, while some labs are processed other labs are free to assign, so while the system updates labs on the queue newly signed up teams can be assigned to labs which are not updated yet.
Demonstration: