If they are doing a rocket run a single lot is very likely. As indicated above even at 100% yield 25 wafers is only 4,525 chips.
IceDrill has bought 250 TH/s of gear. At a nominal 400 GH/s per chip that is 625 chips. They sold another 550 direct and will have to allocate up to 2,200 more for the MPP. So up to 3,375 chips are already allocated.
I assume they will use the excess chips (plus any in the MPP allocation not needed) to either self mine or offer additional sales once pre-orders have been delivered.
That all adds up !
We'll never know whether IceDrill was offered the same MPP, and whether he/she is buying chips or assembled units.
Hashfast have said they will announce multi chip devices in November, and the MPP chips could come from a 2nd production run perhaps ?
IceDrill indicated they were not given the MPP it was for "retail" customers only and they also indicated they will take delivery of raw chips directly.
As for a second run it is possible but unless they intend to do a second rocket run that would be tight to have completed by November so maybe they went with two lots (50 wafers) and that would give them more chips upfront.
They have to save chips for the MPP incase things do go wrong. I'm sure they wouldn't want to be in a position where they offered this program but are unable to honor it because they didn't have the chips.
I know, right? And another batch of chips for warranty & repair ... oh, wait, is the warranty still ten days?