redirects disappearing

I’m using Simple 301 Redirects along with the bulk uploader and it works great, but now I have over 500 redirects and if I edit or add one and click “save,” then about half my redirects just disappear. I can get them back if I reupload my csv file (at least I think they’re all there – I haven’t counted). I’ve seen some old threads here about changing the code to allow more entries – is that still the preferred solution? Thank you!

https://www.ads-software.com/plugins/simple-301-redirects/