Well I can't find any limits on course length either.
And there is no limit on Cpl test validity either.
Only time limit is on the 36 months after your last pass on the theory.
You need to first of all phone back the oxford manager and ask for the exact FCL regulation number.
Also ask that they complete the application and let the CAA decide if they will issue the license or not.
Then if they refuse to give that get some money on your Skype account and do battle with them at the CAA until you can speak to someone senior.
Be warned though they may fob you off and you may have to get legal representation in the UK to start firing off letters to Oxford as the CAA may deem it to be a civil matter.