I want to rewrite the m3u8 output in ffmpeg and change the playback order of divided ts files.

I would like to edit the m3u8 file and change the playback order of the TS file.
If anyone knows how to do it, please let me know.

The assumption is one m3u8 file and several TS files.
If you output ffmpeg in m3u8 format, you get the following results:
The correct condition is to play the TS file towards 1→4 as shown in [1.ts→2.ts→3.ts→4.ts].
Below are the contents of the actual m3u8 file.

#EXTM3U
# ext-x-version —3
# ext-x-media-sequence:0
# ext-x-allow-cache —yes (allows caching).
# ext-x-targetduration:5
# extinf: 4.027222,
test0000.ts
# extinf: 4.004000,
test0001.ts
# extinf: 4.004000,
test0002.ts
# extinf: 4.004000,
test0003.ts
# EXT-X-ENDLIST

We would like to rewrite this m3u8 to the following format to achieve the following:
Suppose you want to play the TS file from 4 to 4 toward 4→1, such as [4.ts→3.ts→2.ts→1.ts].
We edited m3u8 in the intended playback order as follows:
However, the playback of the video doesn't go as expected, and it will harden.

#extm3u.
# ext-x-version —3
# ext-x-media-sequence:0
# ext-x-allow-cache:yes
# ext-x-targetduration:5
# extinf: 4.027222,
test0003.ts
# extinf: 4.004000,
test0002.ts
# extinf: 4.004000,
test0001.ts
# extinf: 4.004000,
test0000.ts 
# EXT-X-ENDLIST

If I want to change the order of TS files like this, how can I edit the m3u8 files?
Or should I re-create the m3u8 file after changing the order of the ts file with the ffmpeg command?

I would be very grateful if you could help me.