Yes, it could be, but the timing fits some plans Cognate laid out last summer that were related to post phase III trial commercialization. It further fits the pace we hear Sawston is at. Also, it fits phase II initiation plans. Finally it fits precommercialization timeline for L. I can't argue with your point the expansion might be something else, but I'm leaning DCVax.
(It looks to me, from various descriptions and posts that May is unit installation month in Sawston and Memphis, does anyone have any information on Fraunhofer and/or King's College?)