There was a term for that, Raid, "M8u" for "upgrade". My chrome M8 got 2/3 of the M8.2 treatment and became a M8u - here are my notes on that service which was triggered by a "column fault" like yours:
5/27/09 Sent off to seller PopFlash for service on vertical blue line 2762 pixels from the left. They sent it on to LeicaUSA for warranty work. And a good time to have two upgrades done also:
• Noise-optimized shutter with a fastest speed of 1/4000s. $1300
• Larger RF mask framelines optimized for 2m subject distance. $1100
• Shutter + Mask upgrade package $1600, less PopFlash 6% discount.
• Health-check and complete adjustment, testing all functions.
• Installation of the newest relevant firmware.
• New factory warranty of one year covering the same conditions as for a new camera. (It had been a refurb from PopFlash 1/1/2008)
Tony phoned Sunday 7/5/09, camera in from New Jersey, $1493 + $15 s&h = $1508 for upgrade package. Great service. Shutter Count when sent in was 8346, and for first shot upon return is 8428, clearly not reset when shutter replaced; 81 actuations while in for service; mine was the 82nd.