Inexplicable payment from PIP after benefits reduced

I'm writing on behalf of my girlfriend, who is disabled and up until recently was receiving PIP. After an assessment went wrong, her PIP was stopped entirely. We are contesting this, and requested a mandatory reconsideration a month and a half ago. The assessment report took her from 8 points to 0, and we were advised by the local law centre that given this it would be expedient to just let the mandatory reconsideration happen as quickly as possible without any serious attempt at making a case and then try to win at the tribunal.

However, a few days ago she received a call from the DWP (though she was not at her phone, so we have no idea what the call was about). In addition, yesterday she received a payment from the DWP. She seems to be hoping that this means the mandatory reconsideration did go in our favour and she is once again recieving PIP. Everyone we've spoken to has stressed the improbability of winning at mandatory reconsideration even if we worked hard to fight at this stage, so I'm wondering if there's a possible alternative explanation?

I ask only because she finds calling the DWP extremely dehumanising and mentally taxing, and I don't want her to have to go through that to find out what's going on only to get her hopes dashed. Knowing the answers she could possibly get back would make it easier, I think, and less demoralising if she doesn't get the result she's hoping for.

Thank you