In the 1980s, before the Internet was available and when commercial online services were expensive, there were still other ways to obtain software besides just going to the store. One way was through disk subscription services. I'm not sure how popular these were on other computers but there were several for Commodore 8-bit computers. The most popular was probably Loadstar.
This particular ad is for one such disk subscription called Uptime. I'm not really familiar with this one and I suspect it didn't last particularly long. At least I don't recall seeing many ads for it. Searching the web, it appears that there were 21 issues of Uptime and that Loadstar actually bought them out at some point. Believe it or not, Loadstar continued to be published until 2007.
Read more: https://www.megalextoria.com/wordpress/index.php/2018/06/01/uptime-commodore-64/
