From The War Zone:

Originally, the ROCAF expected to receive 144 F-16Vs, which are conversions of its existing F-16A/B jets, but this number has since been reduced to 141 through attrition in its existing Viper fleet. Lockheed Martin upgraded the first two ROCAF F-16Vs, the first of which took to the air in October 2015, and these served as pattern aircraft for Taiwan’s Aerospace Industry Development Center (AIDC) to complete the remaining upgrades locally.

Work to retrofit the whole fleet is due for completion by the end of 2023. The next wing to be equipped with the upgraded jets will be the 5th TFW at Hualien Air Base on the northeast coast. While the F-16V name is applied almost universally to these aircraft, AIDC still confusingly refers to them as F-16A/B Block 20 MLUs.