As the title says. Anyone ever tried?

~ Nuadjha, the Briar Fox

You inhale deeply upon your pipe, puckering your lips as you send out three rings of smoke before you, then puff out a small vine of smoke that darts right through all three which causes them to disperse in a hazy shroud!

Ok, so after some quick help in game from Rozy, it is not possible to ensorcell a project either mid-temper or tempered but uncast.

~ Nuadjha, the Briar Fox

You inhale deeply upon your pipe, puckering your lips as you send out three rings of smoke before you, then puff out a small vine of smoke that darts right through all three which causes them to disperse in a hazy shroud!

But it sounds like you can do it between steps?
(i.e. You successfully complete temper/channel cycle #3 of a Major Project, hand it over before pouring the next dose of potion, Ensorcel happens, item gets handed back, and you now pour the next dose.)

There are four (4) states for an item?

'Tempering' is probably what you & I both would call something that is presently curing.
To me, 'tempered but uncast' means that it has completed that process, and is now ready to be channeled at.
'Between tempers' would be the condition that I describned. (i.e. "still a work in progress, but not actively tempering")
'Between Enchants' means an actual usable item (the last thing done was a "final step" successful channel).

Others' interpretations may vary (as ours clearly did, from each other). :)