[-1]: bad array subscript

[wwp]

With subedit 1.2, in bash 4.2.46 (CentOS7), I run:
$ subedit -i file.srt -s 00:00:02,000
and get dozens of:
line 928: [-1]: bad array subscript
plus, the command never completes. When I stop it using CTRL+C, any empty lines at EOF have been removed from file, nothing else.