Hmmm, I didn't think it reset but just stayed in the last position set manually (i.e. the lumbar setting when programming seat memory 1/2 was not recalled later from memory). Maybe I'm wrong and it goes to some 'default' position? Is that what you mean by 'reset'?
2013 x35i (Space Gray, MSport, CW/CWII, DHP, Premium, Premium Sound, Technology, BMW-Apps)
Retired: '09 C300 4Matic, '09 GTI, '06 750i, '05 C55, '04 R32, '03 M5, '02 GTI, '01 M5, '00 M-Coupe, '00 540i/6, '99 M3 Coupe, '98 M3 Coupe, '96 328i,... '86 4000 CS Quattro... too many to list.