Dear [Boss's Name],

I hope this message finds you well. Considering the significant progress we've made on our project and its current stable status, I believe it would be beneficial for me to take some time off to rejuvenate and return with renewed energy.

Additionally, I'd like to discuss the potential for salary adjustments to reflect the added responsibilities I've taken on. Looking forward to our discussion.

Sincerely,
[Your Name]

Dear [Boss's Name],

I hope this message finds you well. I am reaching out to discuss the project deadline. Our team has been diligently working on it, however, due to its complexity and our desire to maintain a high standard of quality, we find ourselves requiring a bit more time.

Could we potentially consider an extension for the deadline to ensure that our deliverables are up to the mark?

Thank you for understanding.
Sincerely,
[Your Name]