When FMQ I prefer to run my thread off the quilt and then start the next part or when there is a design change. I am not the best FMQer but am learning all the time and it takes practice to get it right. I do a lot of "mix and match" where I do some straight line and SiTD and then on other blocks, in a sampler, I will do some FMQ to set things off a bit. There is no written rule for how you work your FMQ. It is totally quilters choice. The more practice the more perfect. I am sure you will find what works the best for yourself.