You really need to take this over to Pepipoo forums.
http://www.pepipoo.com
But you're getting close to their six month time limit. They MUST lay papers at the court within 6 months of the original offence or they miss the opportunity to prosecute. I'm guessing that they are lining up to do this, but if you can delay for a few extra days you might kill it off.
Watch out for the S172 offence - failing to identify the driver - which usually takes place 28 days after the original notice. This may mean they can still do you for S172 even when the 'summons clock' for the speeding has run out.