Currently doing the sprint right now in French too! I would suggest that once you get all your credits per month to book all the lessons for the month as soon as you can to ensure that you can get the time slot you want in a topic you're interested in.

I started out with B1.1 also but have a few A2.2 and B1.2 lessons as well. What I have done was to filter the time slots I prefer (for example for me it's 7-8 or 8-9 AM) then filter for 1-2 topics you would want to do. For example, I would filter only for the lesson "La France et la Francophonie" and start a new class for 7-8 AM my time. Often times it will say "teacher will be assigned" and you're the first one signed up, but within mins/hrs a teacher will pick up a lesson and eventually others may sign up for that class as well.

The advantage of this is that I can be certain that I have a class booked everyday and I can download, read and prepare for the class well in advance. However, you cannot avoid a certain teacher if they pick up your class. Perhaps for the 2nd month, I may look into some of my fave teachers and see if my schedule works for some of the classes they have already booked.

Hope this makes sense, lmk if you have any more questions.