Ok, nine+ days later:
Nine days of varied driving; fast, slow, commute, fun, grocery runs, etc., etc. and no SES light! The longest it went before between resets was 1 1/2 days.
That said, it's easy enough to diagnose the P0455/P0456 as a problem with either the purge valve or the LDP/DMTL canister housing assembly. In both cases (at least with mine) it was simply the 1/4" 'O' ring that is supposed to seal where the electrical connection goes thru the housing of either unit.
Both failed within the same year (6 years old, 72K m.) and neither of them are design to be repaired. (I hate throw-away-and-replace! ) They are both plastic housings that are ultrasonically sealed (melted together).
I was taught by a wise father that there is no such thing as "can't", so I took 'em apart, cleaned up the area, used dielectric grease to seat the "O" rings, and epoxied them back together. So far: success.
I'm a happy panda.
-skip-

 

Hello

Another MINI here with the p0456 code. I've read thru this thread and some people mention that after 6 or 7 "cycles" the light sometimes clears..by cycles you guys mean siting in the car and turning the engine on and off 7 times in a row or having 6 or 7 normal drives...Please pardon my ignorance!

 

IIRC, the codes, if not an ongoing condition, will clear themselves after 3 complete cold-to-normal op. temp-back-to-cold cycles, not simply 3 (or more) incidents of driving the car.

 

Makes sense...Thanks for the response!