Rule 15a: Time to Respond. Unless the court orders otherwise, any required response to an amended pleading must be made within the time remaining to respond to the original pleading or within 14 days after service of the amended pleading, whichever is later.
I'm only licensed in CA. Please note that this answer does not constitute legal advice, and should not be relied on, since each state has different laws, each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.
In addition to the above, take a look at Rule 6(d) Additional Time After Certain Kinds of Service.
"When a party may or must act within a specified time after service and service is made under Rule 5(b)(2)(C), (D), (E), or (F), 3 days are added after the
period would otherwise expire under Rule 6(a).
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