There's a good reason for that. It's because there is no work being done on the detail of transferring the specification of any franchise to TfL.
All that has been agreed is that it will be investigated at some time in the future.
And yet Val Shawcross, Dep Mayor for Transport, told the London Assembly Transport Cttee this week that
a) there were good relations between City Hall and the DfT.
b) the (now former) SoS was very keen to see devolution of services to TfL.
c) that the preferred sequence of transfers remained SET, SWT and then bits of GTR (Southern Metro). 2018 remains the transfer data for SET.
She also added that a large volume of work was underway with Network Rail and a joint investment paper would be put to the TfL Board this Autumn setting out plans (and I assume funding) for a series of interventions to unlock capacity on South London's rail network. No specifics were given as you might expect at this point in time.
I accept that this does not *directly* confirm that work on a service spec is happening for SET but I'd be astonished that an investment programme was being developed independently of a service spec which would allow a base case to be set out and then benefits calculated for the planned interventions. I also fail to see why there has been this sudden adjustment to Thameslink services to run into Kent *if* there was not a wider plan (or spec) for rejigging the SET franchise to allow segregation of inner suburban services for tendering by TfL.