Question: how to convert avhdx to vhdx?
Answer: Select Hyper-V server in Hyper-V Manager. On left-hand side, select Inspect Disk. Browse to location of restored AVHD/AVHDX files. Select one of the AVHD/AVHDX files > OK. Record parent disk name. Repeat steps 2-5 for each AVHD/AVHDX file, and record their order (from newest to oldest)