The REI Base Camp 4 is an awesome tent, I have used it on a couple of trips. Unfortunately, we are currently sold out and I don't know what the availability will be in the near future. With that being said, the REI Co-Op Base Camp 6 is still available. It has almost 25 square feet in additional space, so if you wanted roomier option this would be a great alternative.
If you were specifically set on the 4 person model, I would keep an eye out on REI.COM. I don't have an exact timeline when Base Camp 4 will be available, but it will list online as soon as it does become available. Let us know is we can help out with any additional questions!
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