The area that is taped over with high speed tape is where the upper and lower fairings meet. It’s likely that the upper faring had been removed during overnight maintenance and insufficient time was available for the sealant (used for aerodynamic reasons) to cure before the aircraft was scheduled to re-enter service. It’s a perfectly normal maintenance practice to apply high speed tape over the top of a fillet seal that hasn’t completely cured, it is then usually removed by engineering when the aircraft terminates the next evening.