New laytime and demurrage considerations under sale contracts

The recent case of Profindo Pte Ltd v Abani Trading Pte Ltd [2013] SGHC 10 (Comm) seems to have found, and filled, a gap in the law on sale contract demurrage clauses, and is worth exploring. Where laytime is interrupted during unloading, absent fault from either party, how is demurrage to be calculated between buyer and seller?

Is laytime to be suspended during unloading or otherwise? It is worth noting that the parties were in agreement that the variances between cif and cfr contracts were immaterial for the purposes of the appeal.