Numbering continues in Famous First Edition (DC, 1974 series) for C-26, C-28, C-30, and C-61; and in All-New Collectors' Edition (DC, 1978 series) for issues C-53, C-54, C-55, C-56, C-58, C-60, and C-62.
Generally reprints, with an occasional new story or an occasional all-new issue.
[C-20] Rudolph the Red-Nosed Reindeer tabloid comic is considered to be the first book of this series, even though it doesn't mention LIMITED COLLECTORS' EDITION (but neither does C-24 nor C-50).
Here are the actual indicia titles for this series:
[C-20], C-24, and C-50: "RUDOLPH, THE RED-NOSED REINDEER"
C-22, C-23, C-25, C-27, C-29, C-31 through C-36, C-38 through C-49, C-51, C-52, C-57, and C-59: "LIMITED COLLECTORS' EDITION"
C-37: "LIMITED COLLECTOR'S EDITION" (correct on cover)