I set the length of the test knit by the amount of knitting involved and the difficulty level. All my garment test knits are at least 6 weeks long. 

A bralette is usually 6-8 weeks. 

A fingering weight camisole is usually at least 8 weeks. 

A DK weight sweater is usually around 8-10 weeks depending on how complex it is.

A fingering weight sweater is at least 12 weeks.

I add extra time for particularly complex or burdensome stitch patterns. I also add time if I know it’s a particularly busy time of year (like around the holidays).

Please account for blocking and drying time, so final fit feedback can be shared by the deadline.