If you are placing an exception hold on a cashier's check, certified check, tellers check, US Treasury check, or Postal Service money order (all next day items), because the item appears altered or you have some other "reasonable cause to doubt collectability", what is the maximum length of time you can hold the item? I have read 229.13 h. and the answer is not apparent to me.

US Treasury Check and Postal Money Order - 7 days. Local cashier's and certified checks - 7 days. Non-local cashier's and certified checks - 11 days.

Cashier's checks are next day items.. YOu can only place holds on them for the following reasons, third party checks, deposits not made in person, and large deposit exception...
I don't think you can hold a cashiers check for any other reason...

See 229.13(h) commentary 3rd paragraph. It addresses cashier's checks and says the time may be extended for a reasonable cause to doubt collectibility (appears to be altered would make me doubt collectibility, enough to send for collection instead of accepting for deposit). However, it says the additional hold is added to the local or nonlocal schedule that would apply if based on the location of the paying bank. This appears to say that you can place an extended hold just as for any other local/nonlocal check.