I frequently travel on Gov't issued tickets which include Gov't fares such as YCA, KCA, etc.

Their fare class generally depends on availability at time of reservation. If there is KCA available, they will get that. If not (which is usually the case close in when these reservations are made) then the reservation is in YCA which is indeed a full Y fare basis fare.

These YCA (not KCA, though) fares do indeed upgrade *at time of ticketing* if there is inventory available in the applicable bucket (V/X). It is important to note time of ticketing because often times reservations will be made in advance but tickets not issued until receipt of orders. Once orders are in to the ticketing office, the tickets are generally queued to be ticketed 3 days before departure. They want to get ticketed as soon as possible to use the Medallion status which you are contemplating gifting them.

Yes, they must have Medallion status in order to get the Y-->V/X upgrade at time of ticketing; general members do not get this benefit.

Trust me on this -- I flew up front on Y-->V/X many, many times as an FO and GM thanks to this rule.

My suggestion is to gift to the one that's going to have the most flexibility with scheduling his/her travel arrangements since flexibility to find upgrade inventory certainly helps - for example, one flight might have 0 while another that still works schedule-wise will have inventory.

IF the Y basis upgrade does not clear at time of ticketing, their waitlist receives full Y treatment which means it trumps all other Medallions except those higher Medallions also on full Y or a DM/PM using an SWU. ***NOTE: DL's upgrade coding charts specifically exclude "YCA" from the higher coding; however, DLMatic does *NOT* enforce that at this time. I have witnessed this multiple times first hand.

Hope this helps!