JPEG 2000 data rate

For JPEG 2000 setting in deliver page. In version 14 you could go up to 500 Mb/s for data rate, version 15 only goes to 211 Mb/s
Why is it capped at a lower rate?

I am facing the same limitation. Any info on this would be welcome. I have seen reports that some are getting 500+ Mbit options, but I have tried and no luck.

I am looking for a custom resolution MXF JPEG2000 RGB 12BIT that is higher than 4K - so a 5 or 6K export with a bitrate of 1600Mbit would be perfect for my needs. Tested out a jp2 sequence that has 1200Mbit bitrate (VBR) - new beta 15 handled it really well, realtime playback and all, just sadly no export.