text_combined: london exotica library migration fyi exotic library issue london version different houston version problem bugs london version found temporary solution bugs immediately fixed local level permanent solution london exotic version replaced houston exotic version houston version expected robust sharad london research spending coming week houston sharad back london houston version replace london version approach steven leppard designing regression testing procedure involve fully test similarity two versions procedure expected take least one month commencement hopefully discrepancies found adverse case happens necessary conduct analysis decide wrong necessary testing development take place rodrigo