Upload Speed Is Capped

From BulletProof Wiki

It's very common for DSL/Cable Modem providers to cap upload speeds anywhere from 128 KBit/s to 384 KBit/s. This will affect upload speeds, even though the line is capable of multi-megabit/sec.

The only way to know for sure, is to contact your ISP and ask them if your upload speed has been capped. In many cases, they can provide higher speed service to allow faster transfers.

Unfortunately, there's no way for BulletProof FTP client to circumvent this cap, as it's being limited at the lowest possible level in the TCP/IP protocol.