It may be hard to keep a group to 10 or less people.  A few reasons to try:

Groups of 10 or less will be able to meet constantly in Phases 3, 4 & 5.  We will probably be moving up and down through these phases throughout the Fall.

A group of 6-10 is a great size to get to know one another.  Everyone will have an opportunity to contribute.  This is true both in person and online.  As a group grows, people lose connection and do not feel as valued.  

As you begin, use an easy leadership format.  Leading does not have to be difficult and time consuming.  The simpler it is, the easier it is to teach someone else how to lead the group.  

In your group, identify an apprentice or co-facilitator.  Help them gain confidence in leading.  Quick mentoring steps include: I lead, you watch.  I lead, you help.  You lead, I help.  You lead, I watch.  You lead.   And discuss after each step.

There will be a new leader in 5 meetings and new leaders will have confidence.