Is there any polite way to say this to an author?

There's a wip that I've been following that has gotten insanely popular - over 200 comments on the most recent chapter. The author has so far responded to every comment on each chapter before uploading the next one.

Usually, it takes them a day or two to respond to each comment. The most recent chapter, however, they responded to about half of the comments and haven't responded or uploaded anything since (it's been about a week, which isn't too long but is unusual for them). I'm worried that they're getting overwhelmed with "needing" to respond to everyone and I want to somehow let them know that they don't have to respond to everyone if it's stressful, but I'm concerned that it might come across as rude for the following reasons:

1. They might not feel obligated but truly enjoy responding to every comment
2. There could be a different reason that they haven't commented or uploaded in the last week, even though that's not their usual pattern
3. I'm worried it might come across as me telling them that they need to upload instead of respond to comments, which is not my intention.

Is there any polite way to say this or should I just let this go? How would you feel if someone commented telling you that you don't need to respond to every comment if its too much for you?