First of all, purchasing a ticket costs fare and taxes and FareLock carries a separate service charge. But "purchasing a reservation" doesn't come at a cost at UA.com (not always the case with agents or other carriers), which makes it hard to determine when a reservation is actually purchased when FareLock is utilized.

I see 2 possible interpretations:

* You purchase the reservation at the same time you purchase the Farelock, and you purchase the ticket when you decide to fly (complete the transaction). This gives you the advantages and disadvantages of the CoC from the beginning as you are bound to them from the beginning. You hold the space you reserved while the FareLock is running, but UA can take it away for the reasons they stipulate in the CoC.
* When you purchase FareLock, you don't purchase any reservation or ticket. You do both when you decide to fly (complete the transaction). In this case, the CoC is indeed not applicable and you are 100% subject to the FareLock T&C during the FareLock term, which says that you, the customer, hold nothing more than a "reserved fare". FareLocking does also create a space reservation, but since you didn't purchase any reservation, that reserved space still belongs to UA who will hold it and supposedly transfer it to you when you purchase the reservation. In this case, UA doesn't need the CoC to take your space away, since you don't have any space to begin with. You hold nothing more than a reserved fare.

The second interpretation could be right since it is matches the marketing ("FareLock® lets you hold your reserved fare"). In that case, you're right that the CoC doesn't apply. But as I pointed out above, that doesn't make your case any stronger, it only makes it weaker.

You're free to add your own interpretation as I'm genuinely interested, but please make a strong case for why FareLock *requires* UA to hold space for your non-purchased and non-ticketed reservation, preferably with a reference to the FareLock T&C.