Uncut sheets, did the BEP sell any from 1976 to 1981?

I am just curious when exactly uncut sheets were revived. One person
claims he bought an uncut sheet of $2's, Series 1976 IC block back in
1976/7, I think he said in person at Washington, DC.

A lot of blurbs about these is that they were revived in 1981, which
would defeat that person's claim...unless they did print some ($2
uncut sheets) prior to 1981 to be sold to prospective visitors at the
BEP.

Thanks again!

Nick