From "The Analyst":

HOW WILL AID GET TO UKRAINE?

The $60.8 billion in aid is a little more complex than it sounds. It isn’t all aid to Ukraine in strict terms. $20 billion is to replace what the US Army has taken and already donated. However that can when it comes to items like ammunition for artillery, tanks and bullets for guns, quickly be sent to Ukraine if deemed necessary, under presidential draw down authority.
The remaining $40 billion includes aid for some humanitarian purposes, troop training and payment - just as important as physical aid.
Around $35 billion is available for drawdown of existing military equipment, including M2 Bradley (which has proven to be a pain in Russia’s side), more M-1’s, more M777 artillery, more Palladins, and as many anti-aircraft missiles as the US can supply.
One of the upsides in the delay of providing aid is that there’s already a stock of missiles ready to go. One thing we do know is that ATACMS is now a legal requirement in the bill and more will flow. That could prove to be very significant.
In terms of logistics the US just announced it is sending more advisors to its Embassy in Kyiv to coordinate the secure delivery of new equipment.
Physical transfer can be very quick when it comes to ammunition. For example, the McAlester Army Ammunition Plant in Oklahoma sprawls across 45,000 acres (70 square miles) connected by rail and has a mission to surge as many as 435 shipping containers — each able to carry 15 tons (30,000 pounds) worth of munitions — if ordered by the president in a day.
Much of this will be moved by sea but a great deal will be ferried in by air using the vast military cargo fleet and contracted civilian air freight where needed.
That means ammo can be in Ukrainian hands on the front inside 24-36 hours if it’s necessary.
Allowing for the Senate to pass the bill Tuesday, the President will sign it within an hour and after that, it’s entirely down to how fast aid gets there. My understanding is priorities have been long established and there’s a preferred order for what gets delivered first and what comes later. It just needs the Senate to pass it and a presidential signature.
Finally the tide will start to turn.

Thank you to every American who made this happen.

Slava Ukraini 🇺🇦!