Sec. 17. Valid recorded liens, mortgages, and other encumbrances that are recorded before a principal broker's notice of lien under this chapter have priority over a principal broker's lien under this chapter. Prior recorded liens, mortgages, and encumbrances that have priority under this section include:
(1) a valid mechanic's lien that is recorded after a principal broker's notice of lien under this chapter, but that relates back to a date before the recording date of the principal broker's notice of lien; and
(2) prior recorded liens securing revolving credit and future advances of construction loans.