If there are multiple blank lines between two lists, per normal AWB operation, AWB removes the multiple lines. This causes the lists to become one list. One needs a minimum of two blank lines because just one blank line between list items means the items are part of one list. Unfortunately, it being two separate lists is a minority of cases, majority being the two blank lines should be removed. However, it is better to err on the safe side. This is also requested per part of my BRFA at [[Wikipedia:Bots/Requests for approval#BG19bot 9]]
Examples:
https://en.wikipedia.org/wiki/Transport_in_Bulgaria#Major_roads
https://en.wikipedia.org/wiki/User:Bgwhite/Sandbox1