On the 737, G/S is tracked until flare is initiated at 50 ft AGL. I am not sure if it's smart enough to adjust the flare technique depending on conditions. Did one the other day with a tailwind approaching the limit (10 kts) and it was firm !!
For LOC tracking, I've heard (without finding the source, think it was 737 CBT) that the last 50' LOC tracking is abandoned and current ground track is maintained. Don't quote me on that. Quite common to land a wee bit off center line.