This saying definitely applies to NASCAR's "Silly Season." Silly Season is the time of year when change within teams on the WC and BGN circuits occurs rapidly and frequently. This period traditionally occurred between the first weekend in August and Speedweeks the following February in Daytona. However, the last few years Silly Season has begun earlier and earlier.
Why is it called "Silly Season"? Mostly because of the seemingly ridiculous hirings, firings and/or sponsor/team/manufacturer switches that occur during this period. The driver who declared his undying loyalty to his current team/sponsor/car manufacturer in February is trying desperately nine months later to get out of the deal and get a better one to go elsewhere - usually where there's more wins, more money or more of both.
The ever-growing influx of drivers, teams and sponsors in NASCAR has made Silly Season extend to nearly year-round.
Jay Adamczyk (better known as "Jayski") has created a year-'round
"Silly Season Page" to help us plebian types keep track of all the
changes that occur on the NASCAR Winston Cup circuit. It is located at
http://www.jayski.com/