. . . "The pendency of any such application for reassessment shall not prevent or delay the layout, extension, alteration, widening, change of grade or other improvement of any such highway. [As used in this section, a trial referee means a referee appointed pursuant to subdivision (1) or (2) of subsection (a) of section 52-434 and designated a trial referee pursuant to subsection (b) of said section.] S" . .