I don't know if I understand badly how to use subed or if it is a missing feature.
For example, I open a .srt file and load the video.
There are some subtitles for the first minute of the video.
I press M-SPC to play the video for 2 minutes.
Then I pause the video and I want to insert a subtitle that starts at 2 minutes (the actual timestamp of mpv).
Is it possible to do this?
Each time I use M-i, subed add a new subtitle that starts at the end of the last subtitle (plus a given length) and backward the video accordingly.