Russian combat power continues to shrink

 ISW:

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Russian forces have likely run out of combat-ready reservists, forcing the Russian military command to amalgamate soldiers from many different elements, including private military companies and proxy militias, into ostensibly regular army units and naval infantry. The Ukrainian General Staff reported that approximately 2,500 Russian reservists are training in Belgorod, Voronezh, and Rostov oblasts to reinforce Russian offensive operations in Ukraine. That number of reservists is unlikely to generate enough force to replenish Russian units that have reportedly lost up to 20 percent of staffing in some areas—to say nothing of the battalion tactical group that was largely destroyed recently while attempting to cross the Siverskyi Donets River.[2] The Ukrainian Military Intelligence Directorate stated that Russian forces are conducting covert mobilization and creating new units with newly mobilized personnel who likely have insufficient training to be effective and little motivation to fight.[3] Russian forces also deployed new conscripts from occupied settlements in Donetsk and Luhansk oblasts to maintain an offensive around Kharkiv City, likely due to the lack of Russian reserves.[4]

Russian private military companies are reportedly forming combined units with airborne elements due to significant losses in manpower.[5] Denaturing elite airborne units with mercenaries is shocking, and would be the clearest indication yet that Russia has exhausted its available combat-ready manpower reserves. The Russian 810th Guards Naval Infantry Brigade is reportedly receiving personnel from other Black Sea Fleet units, including navy ship crewmembers.[6] Newly formed or regrouped units are unlikely to be effective in combat.

Russian forces are likely fortifying occupied settlements in southern Ukraine, indicating that the Russians are seeking to establish permanent control in the region. Ukrainian officials reported that Russian forces began digging trenches and building concrete revetments in unspecified areas of Mykolaiv and Kherson Oblast, near Melitopol, and in western Zaporizhia Oblast.[7]
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The Russian military continues to shrink its objectives as it deals with the loss of manpower and equipment.  Russia has lost up to a third of its forces according to some reports.  It is trying to throw surviving troops together in units that have already experienced significant casualties and poor morale.  This might be effective if they were on the defensive in their own country, but it will be difficult to sustain in a failed offensive on foreign soil.