34 m h6 wingspan plus clearance gave 38 m. 63 m minus clearance might give 59 m wingspan. Even if for some reason clearance is given in percentages, wingspan may still be some 56.5 m.
This likely indicates that the H-20 could either be slighly larger than the B-2 (by maintaining the overall shallow sweep wing angle, pure flying-wing configuration), or be significantly larger than the B-2 (some other configuration types, such as cranked kite or pure diamond), given the information we've received on the prospective weaponry loadouts for the H-20.