Sushi changing SRT File Encoding

[Asinin3]

When I ran Sushi with SRT subtitles that were encoded as UTF-8-BOM Sushi saved the output subtitles as simply UTF-8. When trying to open this file in Aegisub it gave the following error:

This is easily fixed by changing the encoding of the file. Weirdly enough, this only seems to happen on SRT subtitles, when I ran Sushi on .ass subtitles which used UTF-8-BOM it did not change the encoding.
Here's the original and sushi output if needed:
sushi.zip

[Asinin3]

As an update, this doesn't happen on all SRT files, only some. I'm not sure what's causing it to happen with the file I provided though.

[averms]

According to subs.py your first comment is in line with the source.
It writes utf-8 when dealing with srt, and utf-8-sig when dealing with ass.
I will open up a pull request to change that behavior.

As an update, this doesn't happen on all SRT files, only some.

Interesting... can you please provide files to reproduce?