Yes. September was the month that many new users discovered the Internet for the first time, because they were given access at University and other higher education establishments, which had many and varied implications.

For instance there was an influx of beginner questions in Usenet groups, questions to which the answer was "please read the FAQ before asking more questions".

There was also just a general influx of activity: groups would see a bump in user numbers and activity that didn't fall back off over time.

New users arrived all through the year of course, but in smaller numbers and tended to be more technically proficient (and aware with network etiquette) to start with because they had sought (and paid for) access for a reason, rather than being given it and being told to go explore.

From 1993 onwards the public more generally were becoming a lot more aware of the Internet and being told about the things it could potentially do for them, so there was a more constant flow of new (often relatively non-technical) users & activity rather than just a big glut each September, which is why that year was referred to as "the September that never ended".