Browsing Slater's website (which has recently been revised to include G3 items), I see that a Midland brass safety valve cover has been added:-
XG30708 Midland Railway Safety Valve Cover (cast brass) £12.00 (inc. VAT)
Could this be an indication that the Kirtley 0-6-0 is getting close to release?
Incidentally, since my previous message regarding Slater's full range of wheels not being stocked by GRS .... I noted at the AGM that they do now have most, if not all, in stock.... they certainly now have the Slater's 3-hole wagon wheels which Slater's had earlier told me "GRS didn't want"!