I'm seeing I space on EWR-MAN and EWR-GVA on 4/19, as well as on LH EWR/JFK-FRA, and intriguingly enough on the LO JFK-BUD flight, which is probably the most interesting of the lot.
Also if you don't mind positioning to ORD or BOS there's O space on both LH ORD-FRA flights, ORD-MUC, as well as BOS-FRA and -MUC (both of which have empty F cabins now) — and you could add on an intra-Europe leg to get the FCT in FRA / FCL in MUC and to where you actually want to go.