Given what Rep. Nunes and his opposite number Rep. Schiff have seen, it begins to look like Trump wasn't far off when he claimed wiretapping. And it was intentional wiretapping, although perhaps only indirectly of him and his people.
One guesses that Trump was reacting to inside stuff being known by Obama folks that his people hadn't shared with anyone outside. It was logical for him to call it wiretapping, even if that wasn't technically what had happened.
And at this point we don't know if the material he reacted to were extracts from routine intercepts of foreign diplos. Perhaps foreigners thought to have inside info about Team Trump were targeted for that reason.
The U.S. isn't the only country eavesdropping on persons of interest. The possibility remains that Trump's people were actually wiretapped by foreigners - MI6 or equivalent. Their work product was then intercepted and decoded by NSA, no FISA permit required.
It is conceivable a foreign agency wiretapped Trump Tower at the request of NSA or CIA, again no FISA permit required, perhaps as part of a tit-for-tat deal: you eavesdrop on our opposition, we'll eavesdrop on yours, and we'll trade recordings. Subcontracting out dirty work is a fine old intel tradition, everybody does it.