It is risky to rely on procedural missteps by the LL because you might get a "law and order" judge. Having said that, since the UD procedures are expedited and can result in a tenant losing their living place, most judges hold LL close to the mark and don't let them proceed unless every "i" is dotted and every "t" crossed. You should consult with a landlord/tenant attorney ASAP. Some might give you a free consultation.
It is not clear what "response" you filed to the unlawful detainer lawsuit. Was it a verified Answer to Complaint, and did it raise the appropriate affirmative defenses? Without knowing what denials and defenses you raised, it is not possible to tell you what to do. Keep in mind that if your lease is up on March 30th anyway, the landlord already has the right to file an unlawful detainer lawsuit against you WITHOUT any notice.
Frank W. Chen has been licensed to practice law in California since 1988. The information presented here is general in nature and is not intended, nor should be construed, as legal advice for a particular case. This Avvo.com posting does not create any attorney-client relationship with the author. For specific advice about your particular situation, please consult with your own attorney.
The important question here is what did you say in your response? Did you raise a defense that service of the 3-day notice was defective? If you did not you may have waived that defense because you have made what is called a general appearance. As Attorney Chan states your lease is up March 30th and notice may not be required.
Contact an attorney in your area many, such as myself, offer free consultations.
Note this answer does not constitute legal advice, and should not be relied on. Each situation is fact specific and court specific, and it is not possible to evaluate a legal problem without a comprehensive consultation and review of all the facts and court pleadings filed in the case. This answer does not create an attorney-client relationship