At the dual risk of stating the obvious as well as beating a dead equine, I'd like to make a further point about Eph 2:20. Metaphors are open-textured. They often have a wide range of potential connotations. So we need to distinguish between potential connotations and actual connotations, which are a subset of the potential connotations. The actual connotations are determined by the author.
A theological metaphor is a figurative analogy. And a theological metaphor is a controlled analogy.
What the metaphor means depends on how it functions in the author's poem or argument. Sometimes that can be determined by context. Oftentimes a Bible writer is recycling a stock metaphor. He takes for granted the idiomatic force of that metaphor in established usage.
Cessationists infer chronology from the foundational metaphor in Eph 2:20. In a construction project, the foundation is laid first and laid once. But there are several problems with that inference. I'll focus on two (i've discuss a third in another recent post):
i) You cann't treat a metaphor as an autonomous unit of meaning, where all the potential connotations are in play. An author doesn't intend all of the potential connotations. He trades on some connotations while suppressing others.
ii) The tactic backfires, because it's child's play for a continuationist to do the same thing. He can easily turn the cessationist prooftext into a charismatic prooftext by simply developing a different connotation of the same metaphor. In this case, he infers from the relationship between the foundation and the superstructure that the apostles and/or prophets continue in perpetuity for the duration of the church age. After all, the foundation supports the upper stories. If apostles and/or prophets are temporary, that means the foundation in temporary, in which case the superstructure will collapse. This inference is no more or less legitimate than the cessationist inference. And cessationists are blindsided by this countermove.
To take a comparison, suppose a Mormon apologist or Muslim polemicist treated the Fatherhood of God with the same freedom as cessationists treat the foundation of the church. Fathers come into being. Fathers have mothers and fathers. Fathers have wives. Fathers are physical. Fathers are finite in knowledge and power. Fathers grow old and die.
Orthodox cessationists have no difficulty understanding what's illicit about that inference when it comes to the Fatherhood of God, but their reflexive animosity to continuationism disarms their critical judgment when it comes to Eph 2:20.
BTW, taking Eph 2:20 off the table is not a decisive win for continuationism. It's just one less prooftext for cessationism. Your case is pretty weak if it can't survive the loss of one prooftext.