U.S.-based L-visa applicants are not currently required to provide an invitation letter; use a truthful not-applicable explanation instead of inventing a China host.
Do not edit a JW form yourself or assume two passports cure the mismatch; ask the school to update or formally link the record and confirm the responsible U.S. Visa Office's instruction.
For a U.S. passport, follow the data page and identify the issuing authority—normally the U.S. Department of State—rather than a post office, acceptance facility, birthplace or current state.
A valid second U.S. passport can be the application passport if it meets China's published validity and blank-page rules, but one passport number must stay consistent through COVA and submission.
No current Chinese U.S. mission guidance publishes an automatic delay or interview rule for Turkey stamps; applicants should report travel history truthfully and prepare for case-specific review.
The correct visa depends on what the camp actually does: tourism points to L, an exchange or study tour may point to F, and formal short-term study of 180 days or less points to X2.
After Z-visa COVA review reaches “Passport to be submitted,” bring the passport, printed barcode page and every original specifically requested by the responsible U.S. visa office.
A short U.S. visit does not automatically qualify a foreign passport holder to file through a U.S. Chinese mission, which requires residence in its jurisdiction and proof of lawful U.S. status.
Choose L for a genuine tourism trip and M when planned meetings, supplier research, trade fairs or other commercial activity are the trip's real purpose.