R12.1.3 Project Expenditures - where is Bill Rate pulled from?

Hi,

We are using R12.1.3. I have an issue with a project, where the Expenditure Items created against the Project used to have a Bill Rate value of 1 against them - here's a summary:

You can see that between 5th June 2018 and 12th Nov 2018, 759 Exp Items were created with a Bill Rate of 1.

Then from 4th Oct 2019 onwards, the Bill Rate has been zero.

Here are two example Exp Items:

In this case, on the WebADI upload template, there is no option to set the Bill Rate:

Though - the issue also happens for exp items created from AP costs as per the SQL Developer screenshot at the top of this post.