Received an update from CentralDS late yesterday. The debayering of my 450D sensor is complete and the unit has been tested, and is ready to return. Yun Lee advised that the Canon image sensor wafer characteristics are not all the same, and up until my 450D they had only debayered 600d, 5d and 6d sensors. As they did not have experience with the 450D sensor they elected to bring in two 450D sensors for testing prior to starting mine - this is what has taken so long (the delivery of the two test units). The test units arrived this week. The CentralDS debayering process is based on a chemical solution to strip away the bayer matrix and micro lenses without scratching the surface of the sensor - unlike the process formerly used by JTW and others, which involves scraping off which can scratch the sensor and had the potential of breaking the gold wires on the edges. So after testing their chemical stripping process on the test 450Ds and finding that their process worked and the units tested OK afterwards, they went ahead and debayered my sensor. My sensor passed the QA testing and is now ready to return ship.
Here is a link to the CentralDS writeup on their debayering process, with examples of mono resolution improvements:
http://www.centralds.net/cam/?p=8561
I will be keen to test it out once I get it back. More soon.