Think you should check your last post Shaun!!!! and yes I certainly do know about the alternative ways of applying product to leather and possible / probable outcomes.
On this occasion the change in colour is only a couple of shades, nothing dramatic, so using the standard procedure would do the job, quickly and safely.
As far as other products / variations of products is concerned, yes spraying can be done, I've been aware of that for some time, but always consider the safest and proven method first.
peace and prosperity