On Page 11 you will find:
In order to comply with the funding rules, each apprentice should have a commitment statement that, amongst other information, outlines the programme of training that the apprentice should receive. This statement should set out how the provider intends to fulfil the 20% off-the-job training requirement. As set out in the funding rules, the funding recipient (usually the main provider) is the custodian of the relevant evidence files.
The detail in commitment statement and the evidence for a minimum of 20% OTJT up to the point the Apprentice withdraws is what auditors will be looking for.