Tapakeg...
Under standard FISA rules, the NSA/CIA could start a wiretap immediatly and had 72 hours to bring it to FISA to get the official ok. In addition to that... there is even a provision that allows the Federal Government to go up to 90 days with "good cause" before presenting to FISA why they are tapping a line, they would simply need to justify why it was necessary. Now if those tools aren't good enough, i don't know what is.
If after 3 days of listening and however months of investigating in the first place they can't get approval... or if they opt for the 90 day delay and then present and can't get it... well then maybe they shouldn't be listening.
A little oversight never hurt anybody.