Joffe appear to have gotten the rights to at least the first four books in Dolores Gordon-Smith's Jack Haldean historical series, which I've quite liked. So expect some sale prices on those. Right now, the first one,
A Fête Worse Than Death, is $0.99/£0.99 at Kindle US/UK. But I also suspect there may be a box set coming, since Joffe often does box sets.
Also, check carefully before you buy, because there are earlier Severn House e-book versions of these that won't show up as purchased...
Kindle US:
https://www.amazon.com/dp/B0CB8PDK2Y
Kindle UK:
https://www.amazon.co.uk/dp/B0CB8PDK2Y