Ukraine

Not to go down the rabbit hole but DU armor is an addon or sandwich to most Chobham armor packs in the M1. However, I believe (needs verification) but US law prohibits the export of Depleted Uranium in some products, like tanks (to certain countries). Therefore, most but not all M1's exported have tungsten armor in place of DU. Chobham armor is a manufacturing process to harden the steel (again I believe) and then sandwiched with DU for US tanks and tungsten for export versions. Depending on which expert you speak with including Europeans the tungsten sandwich is just as effective as the DU. The reason most European tanks have tungsten is because the aversion to burning tanks loaded with radioactive DU all over Europe (in the event of WWIII). However, since US tanks have it, it's the price for US shouldering the defense of central Europe. I guess the thought of the Russian hordes advancing over the central European plains was enough to sway the Germans to allow DU armor in the US Tanks defending them. However, German tanks do not use DU armor.
Ukrainian tanks will most certainly not have DU armor (nor would they get DU sabot rounds) but may have tungsten.
Also I believe that the US Marines operated M1A1's upgraded to 120mm back in the Mid 2000's? So an "M1" might be a general media term for any "Abrams" tank. I would tend to think that the 105mm are a bit of a rare bird? Even back in the late 1990's the Guard was up gunning to M1A1's. I can't see the US supplying 105mm equipped tanks when the NATO standard is 120mm?
That's the problem it's a both a general media term and a specific model type term. Some of the detailed specifics are here: https://en.wikipedia.org/wiki/M1_Abrams

One should not make assumptions if the US Marine Corp is involved. Hand a Marine a cannon ball and he or she will either break it or drop it overboard.

The US Army and all of its guard units are still US Army, they probably have not had the rifled 105mm for years. But up until the Marine Corp dropped tanks altogether two years ago, their old M1 were armed with 105mm's.

I suppose it came down to a fact that Marine Corp gunnies did not approve of smooth bore guns of any type.

The M1 came first, then the M1A1, and then the M1A2. It's confusing though because some people use the shortened term M1 to mean any of, or all of the variants.

Unless it was added on later during a refurbishment the original M1 didn't have depleted Uranium armor, and had only the 105mm gun in a smaller turret. The original M1's were produced between 1979 and 1985, and about 3,000 of them were made.

I think most of the original M1's have either been scrapped, or have been re-manufactured into the larger heaver M1A1 and M1A2 variants by replacing their turret and adding armor to the chassis.

Details of Chobham armor and depleted Uranium armor are both still secrets, but are probably both layered armor. Chobham being layers of steel ceramic with perhaps elastic layers in there as well. Depleted Uranium perhaps the same but with Uranium alloy steel replacing the ceramic.

As I understand it Chobham is the original armor for the M1, and is still the base armor of the later M1 variants when depleted armor is overlaid on top of base Chobham armor.