James, the advice from Bigal (a former examiner for the OR's office) on the BR forum is that this is and administrative error:
I'd like to add a bit more about the notion of £0 IPA's.
These came about, mainly due to some examiners making the wrong selection when completing the IPA agreement.
When the examiner uses the insolvency service system to set up an IPA, they normally get 3 options, namely: IPA only, NTIPA only or IPA and NTIPA( where NTIPA is the tax element to be collected up to the end of the tax year).
What has happened in the past is that when an NTIPA only was required,some examiners chose the IPA and NTIPA option, which would then produce a template to fill in the relevant information i.e. tax normally collected, but because it would also ask for the IPA amount(when one wasn't being raised) the examiner would put in £0, thus when the agreement was printed off, it would show the NTIPA amount, but also an IPA amount of £0 over 36 months, which is what had been put in because the template was asking for it.
It was never a sneaky way of the OR getting people signed up for IPA's just in case!