Hello all.
I am a total newbie to tiles and this should not be considered advice - just my experience.
I tried soaking tiles in hot water ans it did make the adhesive softer, but still hardwork. I tried putting them on an old baking tray and baking them in the oven for 1/2 hour hour at 220 degrees C, and the adhesive just fell of like crumbling cement. It took me about 2 minutes to clean each tile with a chisel once it was hot.
I advise your open the windows to your kitchen before doing it, as the process makes a smell much like soldering copper pipes together.
Thanks to all for putting this post up, as it was your advise that has lead to this HUGE time saving for me. Many thanks indeed.
Newbie.