This is one of those basic pattern pieces that gets copied and altered many many times. The following notes are based on Ertz 1979.
A variant not mentioned by Ertz (and a very bad one, too) formerly in the Dragor collection, Denmark, col. G. Sadolin [RKD JB L1]. Two more unmentioned but OK variants are: formerly art market, Paris (Charpentier, 12.v.48 #27, panel, 20 X 30.5) and formerly art market, Paris (Galliera 20.vi.61 #66, copper, 21 x 22). Variants Ertz does list are his #106 in Toledo from 1604 (see below) and his #95 in Turin dated perhaps 1603 which isn't really a variant. Then there are three more possibilities--ones he doubts attribution of but could be studio variants: his #141 is indeed a quite close take-off of this Wellington painting, while the other two he doesn't illustrate. There are also two works he identifies as variants by "followers", one in Amsterdam and other in a private collection. The Amsterdam one is now identified by Ertz as a Jan the Younger (Ertz JBII #31: copper, 14.5 x 20.5; RKD BL1 as JBI) supposedly done before Jan the Younger left for Italy. One of these copies was sold Sotheby's London December 5 2007 as being by a follower/studio of JB, with its pendant Ertz #152, also on copper and dated 1607. This is exactly the sort of work that could be by the studio. It really isn't a copy at all of the Wellington picture but a quite bad pastich-y variant.
Condition: small areas of damage upper right and left, otherwise good (from collection catalog). I have changed measurements from Ertz's to match those given by the Wellington museum itself. They also note that the last 2 digits of the date are not easy to discern.