They are included in the Dec 22 rewrite.
However the political decision is looking somewhat shaky. General assumption is that the longer everyone holds their breath, the more likely it is that Grand Union will fold out.
The already dubious business case now looks febrile at best. The mk4s they were going to use are quickly disappearing to TfW or scrap, or staying with LNER for the forseeable. The incoming GBR is likely to take a dim view of new open access operators for the first year or so while kinks are ironed out.
There are other issues with power supply, occupying a platform at Stirling for potentially 2 hours at a time, traction (potentially the hypothetical cl 93s which I'm still somewhat certain we'll never actually see) ect.
I'm not saying it will never happen, but I'd put a hundred quid on the Grand Union Trains Stirling service never turning a wheel in anger.
(Furthermore, the intended start date of May 2021 now seems laughable, and the website hasn't been updated in at least a year at this point)