Note that the checksums are different for those 2 versions (SHA256) I believe the older one (the 12th date one) may be the base version, and then it gets 'polished up' and released on the builds page perhaps.
CCleaner v6.35.11488 (16 Apr 2025) https://www.ccleaner.com/ccleaner/download Version history = https://www.ccleaner.com/ccleaner/version-history
CCleaner v6.35.11488 Spoiler: Direct Download Links Free https://download.ccleaner.com/ccsetup635.exe https://bits.avcdn.net/productfamily_CCLEANER/insttype_FREE/platform_WIN_PIR/installertype_ONLINE/build_RELEASE Slim https://download.ccleaner.com/slim/ccsetup635_slim.exe https://bits.avcdn.net/productfamily_CCLEANER/insttype_SLIM/platform_WIN_PIR/installertype_ONLINE/build_RELEASE Portable https://download.ccleaner.com/portable/ccsetup635.zip Professional https://download.ccleaner.com/professional/ccsetup635_pro.exe https://bits.avcdn.net/productfamily_CCLEANER/insttype_PRO/platform_WIN_PIR/installertype_ONLINE/build_RELEASE Technician https://download.ccleaner.com/te/ccsetup635_te.exe https://bits.avcdn.net/productfamily_CCLEANER/insttype_TECHNICIAN/platform_WIN_PIR/installertype_ONLINE/build_RELEASE Business https://download.ccleaner.com/be/ccsetup635_be.exe https://bits.avcdn.net/productfamily_CCLEANER/insttype_BUSINESS/platform_WIN_PIR/installertype_ONLINE/build_RELEASE
By the way, at the moment the portable zip file of the latest build v6.35.1148, is not downloadable from the builds page. https://www.ccleaner.com/ccleaner/builds They forgot to include the dot before the zip extension so you have to paste it into the address bar yourself. https://download.ccleaner.com/portable/ccsetup635.zip
i'm version 6.35 11488 as no but if you have the updates set it will auto update it when you use the program. mine just did, fyi