Summary
In an alphabetical list, the letter "i" is interpreted as 1 in. I assume it is interpreted as the roman numeral for 1. This is tested with reST.
Code snippet that reproduces the problem
...
g. Seventh
h. Eight
i. Ninth
Expected output
...
g. Seventh
h. Eight
i. Ninth
Instead, the output is:
...
a. Seventh
a. Eight
1. Ninth
The two "a"s are caused by issue #1251 and are separate.