@zach and @olegkhr This issue I am experiencing seems to have many of the characteristics raised in Problem with sending short TCP packets on Electron olegkhr is using FTPino I was originally using ParticleFTPClient https://github.com/jychuah/ParticleFtpClient which I have ended up writing my own FTP client to try and get to the bottom of what is happening.
There is definitely an issue with TCPClient sending short packets of data.
I have not been able to solve it. I have sidetracked to see if I could use the AT commands on the ublox modem but I am suspecting that Cellular.command() is not capable of the streaming data that I need. Others have found a solution ie @mountainecho [SOLVED] - General-purpose read from modem serial and Electron: Direct Access to Cellular Module through USART has tried to access Serial3 and talk direct to the ublox but these all involve hacking the firmware and compiling it locally etc.This I was trying to avoid.
It seems that there is enough evidence to raise a firmware bug at this point?
Would it be possible to allow access to Serial3 in exactly the same way as we have access to Serial1 etc? This would allow direct access to the ublox to remove the limitations imposed by Cellular.connect()
Thanks for any help you can give Particle team.