There is no such thing as an H1B transfer. Whey you leave the employment of the sponsoring employer, that H1B will be terminated. Your new employer can apply for a new H1B. If you do so in a timely manner you can avoid certain steps like worrying about the cap.

If by "taking a break for a year" it means you're going to leave the US, that's not a problem, but you'll be starting from scratch when you return. If you mean you are going to stay here and accumulate unlawful presence without another visa application in process to hold this in abeyance, then the answer is NO there is nothing you can do to make that legitimate.

The other fearful thing in your post is you talk about being jobbed out to a specific client. THIS IS NOT WHAT H1B is for. I have serious doubts about the validity of your current visa.