I have argued previously that the day of the Lord will not be a simple, literal 24-hour day, as many postribulationists claim. The day of the Lord will be a complex-whole when God works out his purposes of deliverance of his people and judgment upon the ungodly over an extended period of time, beginning with the seventh seal, trumpets, concluding with the bowls.
I noticed another explicit statement that precludes a literal 24-hour day, the “in the days.” I have read it many times, but it never registered until recently:
“But in the days when the seventh angel is about to blow his trumpet, the mystery of God is completed, just as he has proclaimed to his servants the prophets.” (Rev 10:7).