Your own risk.
What if the secondary of the input transformer is connected to a positive potential such as Vb (or even anode?) then the other terminal of the secondary connected to the Pleiades bias resitor. The other side of the resistor to control grid. A capacitor then connected in parallel to the grid Pleiadss bias resistor.
So this is grid leak bias but connected to a more positive terminal than the cathode making again electron tube operation possible at very low anode voltage.
There may be rectification side chain compressing effect at high levels. Just what happens when the Neumann U47 microphone VF14 electron tube circuit is overdriven and bias changes automatically reducing gain. See other euroelectron posts. The release time may be fast since the input impedance looking at the grid when Pleiades bias is applied is typically 100KΩ. So the interested reader sound find more suitable examples on the original U47 Neumann circuit featuring resistors of many megohms, Western Electric small signal amplifying circuits, and on the book Communication Engineering - Everitt in the section of resistance coupled, transformer coupled amplifiers.
The grid leak bias is also used for example on Emerson vintage electron tube portable gramophone amplifiers for producing great bass utilizing the property of the human brain to synthesize a missing fundamental from the presence of overtones. See older posts.
Reference:
The Neumann U47 microphone BBC report:
https://www.bbc.co.uk/rd/publications/rdreport_1954_23
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