Thanks to a Freedom of Information Request, the answer to which has been published today, it is finally possible to map the sub-unit structure of the Royal Logistic Corps of Army 2020.
1 Regiment, 3 Regiment and 4 Regiment are Close Support Logistic regiments, part of 101 Logistic Brigade and assigned to the Reaction Force. They are aligned respectively with 20th, 12th and 1st Armoured Infantry Brigades.
9 Regiment, 27 Regiment and 10 The Queen's Own Gurkha Logistic Regiment are Theatre Logistic Regiments, again assigned to 101 Log Bde in the Reaction Force and aligned with the three Armoured Infantry Brigades. 27 Regiment contains the last remaining Tank Transporter squadron in the army. This particular sub-unit, for obvious reasons, supports all of the heavy brigades.
6 and 7 Regiments are described as Force Logistic Regiments and are assigned to the Adaptable Force, staying under 102 Logistic Brigade. They are meant to provide the logistic element of the Adaptable Brigades which get deployed in the fourth and fifth tour of an enduring operation abroad.
The list does not include 132 Aviation Support Squadron, which supports the Army Air Corps and is part of 7 REME battalion. The RLC involvment in the Royal Marines Commando Logistic Regiment (the Log Sp Sqn within the regiment) is also not detailed for some reason.
Interestingly, there is no 65 Squadron listed within 13 Air Assault Regiment. The squadron was brought under command in July 2013, and 15 Air Assault Squadron was disbanded as a consequence. Now 65 Logistic Support Sqn is nowhere to be seen, for some reason.
UPDATE: i've received confirmation that 65 Sqn remains active and in 13 Air Assault Regiment. For some reason, the list is not complete in this regard.