Retirement tax questions

Thank you, @dmertz ! I was indeed referring to the 2022 tax year. Unfortunately, I've just learned that the IRA contribution deadline remains April 15th even with a filed tax extension, so I missed that opportunity. However, I believe the contribution deadline for solo 401k deferrals and employer matches for a pass-through single-member LLC is extended until October 16th with a tax extension filed in April, correct?