This group is for people who notice canononical contradictions within popular sci-fi and fantasy franchises and wish to discuss them in a safe, TROLL FREE, environment.
So as you can tell, there were a million clones readily available at the start of the war. when prime minister Lama Su said "10,000 units are ready with a million more well on the way" he was referring to the number of "Combat ready" clones. there were a million full grown clones but only 10,000 were ready for full scale combat.
Now on the previously established timeline, SW:CW starts at 21.66 BBY (4 months after the battle of Geonosis) with the battle of muunilinst. Four months is an adequate amount of time to train the remaining clones. Let us also remember that on the more distant worlds, the clone war is being fought by militia with small clone detachments in support. during the first few months of the war full clone armies are reserved for high value targets which Muunilinst is.
So as you can see it WAS completely, logistically possible for the large scale battles seen in the Miniseries to take place.
however with Leeland Chee's condensing of a large number of events (including the events seen in the first volume of the SW:CW miniseries)into a span of a few months, the logistics behind the battles of the miniseries being previously possible may no longer be the case. you can thank TCW for complicating that.
Now the whole clone wars debate aside. It is stated in many many sources that the number of clones is still unestablished because the units can mean many many things. This one million strong line could be interpreted as the one million are the 10,000 units of 100 clones each or it could be just as you read it. One million clones. It is widely believed that the 10,000 units was actually referring to a much larger number of actual clones.
However, the Kaminoans sometimes did use the term "unit" to refer to an individual clone (as revealed in the Republic Commando books when talking about "defective units" i.e. the Null ARCs). Just food for thought.
However commando units can refer to a smaller unit than regular clones. When I was in the Army a regular company of soldiers consisted of 3 platoons each with 3 squads of 9 men plus various command personel making it about 90 men. The Recon company I was in was basically a special forces unit and we had only about 30 men breaking down in to 4 recon teams plus command personel. Point being the Kominoans could have a completely different way of refering to a commando "unit" as opposed to a regular clone "unit".
The problem is unit is a very basic way to refer to something and its even possible their use of the word like our own use is used interchangeably. The context in which you describe is very clearly referring to a single clone but the context in which it is said in Ep 2 is not fully understood. This is why the whole subject is still openly debated. :)