My reservations (plural) have been unaffected to date on the Capitol Limited. But I also chose to book the lowest sleeping car number, which is the sleeper next to the diner. Typically if Amtrak takes a sleeper car off they re-arrange those in the higher car number. If the Capitol's consist was programmed with TWO sleepers, Amtrak's been taking the second sleeper OUT of the system (be it a full Superliner Sleeper or Superliner Trans/Dorm Sleeper), now that there's a run-through operation going on between Capitol Limited and Texas Eagle. At least ONE Superliner Sleeper is still there in the consist. With that adjustment though, there are MANY days now that the Capitol Limited is SOLD OUT in sleeper class. Demand certainly exceed capacity. Amtrak doesn't seem to care. Even when going tri-weekly, the Capitol started out with one Superliner Sleeper, but then it got so bad that they did add either a full Superliner Sleeper or Superliner Trans-Dorm Sleeper to ease congestion even from misconnects.
Right now though, eastbound there's only like one day between now and April 15th with a sleeper accommodation available, and just as bad as westbound. The Capitol Limited's demand, despite what Amtrak has said over the years, has ALWAYS warranted at least TWO Superliner sleepers AND Superliner Trans-Dorm Sleeper space being sold April through October. I've been onboard when Amtrak has even added a third sleeper for a couple of months. They save a train set in the run-through operation, but they've done nothing to increase capacity.