Kraig Biocraft Laboratories Inc (KBLB)

[RetroTire]

"Second and subsequent extensions" have an additional requirement over the first extension in that the party "must include a statement of the applicant's ongoing efforts to make use of the mark in commerce..." according to 37 C.F.R. 2.89(b) explained in (d) under the T.M.E.P. 1108.02 Requirements for Request For An Extension of Time to file a Statement of Use.

I would guess that the review of this statement of the applicant's ongoing efforts may be the extra time required.